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March 22

Do mind altering medication really work?

Like anti anxiety pills, anti depressants. I've read lots of people say it does nothing. I used quite a number of anti depressants and all I feel is sleepy. I also used phenibut and it does NOTHING. I feel like they are all scam by greedy pharmaceutical companies. Has there been any investigation into the effectiveness of mind altering medicine? If you know any articles please link. Thanks. Money is tight (talk) 07:59, 22 March 2017 (UTC)

Drugs work differently in different people, but they must all be tested thoroughly before being put on the market. Their effectiveness is discussed in detail at antidepressant.--Shantavira|feed me 08:08, 22 March 2017 (UTC)
• I'm sorry, but even the most casual search would turn up thousands of hits on this subject (antidepressant + effectiveness alone gives me 3851 hits on PubMed this morning), what exactly are you expecting us to give you here? You might have to narrow down your question. Let me add that, as a neurobiologist, I find your assessment that these drugs are 'all scam' somewhat of a professional insult, you may also want to rephrase your question in a less inflammatory manner if you want more answers. Fgf10 (talk) 08:15, 22 March 2017 (UTC)
• While, as for any medicine, "authorized to market" is different from "working", the idea that it is all a big scam is a conspiracy theory, for which I've read lots of people say... I feel like... is not sufficient supporting evidence. TigraanClick here to contact me 08:34, 22 March 2017 (UTC)
• If a particular medication is not doing the trick for you, it's your responsibility to inform your doctor so that he can try something else. And if he runs out of options, try another doctor. ←Baseball Bugs What's up, Doc? carrots→ 08:54, 22 March 2017 (UTC)
• "I've read lots of people say..." -- are any of those people real doctors in the relevant field? And how many of them want to sell you a "natural solution"...? And wouldn't it make sense for a medication affecting something like the mind to have as subtle an effect as possible? It kinda defeats the point of taking an antipsychotic if it's followed a booming chorus of voices in your head shouting "YOUR MEDICATION IS NOW WORKING. YOU NO LONGER HEAR ANY VOICES IN YOUR HEAD BUT YOUR OWN. ENJOY THINKING YOUR OWN THOUGHTS UNINTERRUPTED." Ian.thomson (talk) 09:37, 22 March 2017 (UTC)
• It is often recognized that other complementary services (proper followup, counselling and therapies), other than medication alone, can enhance the prospect of recovery. If the time period for readaptation is longer than a few years, there is more possibility of long-term medication. Unfortunately not everyone can get an ideal treatment, partly for economic reasons. This does not preclude that these medications have a measurable effect on the brain. See the selective serotonin reuptake inhibitor article for instance, on a specific class of drugs commonly prescribed as antidepressants and sometimes as anxiolytics. Of course, other anxiolytics like benzodiazepines, and antipsychotic drugs, are quite different, and some medications are not advised for long term or regular use. Unfortunately, nothing being perfect, and with the wide array of individual biological factors, what works well for a person may not give the same effect on another. There also are side effects, with individual variation on which are felt more or less (they can affect health and mood). Other issues are adaptation of the body after repeated regular use, and its recovery (withdrawal) when the drug is interrupted (which is why many medications must be introduced and stopped gradually). The withdrawal symptoms of some medications can be very discomforting and sometimes life-threatening (which would not be the case if they did not successfully alter brain chemistry, BTW). Drugs that are on the market have been tested carefully versus placebo (not only for subjective sensations of subjects, but using blood tests, and sometimes magnetic resonance imaging and other methods). They are a result of a number of years of scientific and technological development. When possible, newer molecules are used which are more specific than previous ones to more effectively target wanted neurotransmitters or receptors than previous drug generations could, also reducing side effects as possible. PaleoNeonate (talk) 10:54, 22 March 2017 (UTC)
In order to bring a medication to the market a pharmaceutical company must prove its effectiveness in clinical trials while comparing the medicine to placebo. The trials typically last 3 months and involve a few hundred people. They are double blind. Nobody knows individual result until the very end. The whole trial typically costs upward of a billion dollars. Before the clinical trial the company must test the medication on animals, bacteria, etc. All FDA approved medications including antidepressants are effective albeit not everyone will respond. There are treatment resistant cases. Some people sabotage their own treatment because they like to complain and project an aura of misery. --AboutFace 22 (talk) 14:14, 22 March 2017 (UTC)
Citation needed for "a billion dollars". --76.71.6.254 (talk) 14:37, 22 March 2017 (UTC)
From Forbes, $4bn to$11bn total cost for every new drug approved (counting failures), and "combined cost of manufacturing and clinical testing for some drugs has added up to $1 billion". And that was five years ago. — Lomn 15:54, 22 March 2017 (UTC) [EC] Seconded:$1 billion is in the ballpark for the total costs of all the testing and trialling required to take a single "candidate molecule" from initial identification to the market (under the regulations of the FDA, which tend to dominate the global Pharmaceutical industry). The particular type of clinical trial described by AboutFace 22 above occurs in Phase 2 of the process, which has 4 phases (0–3: Phase 4 is post-release monitoring) and typically takes around a decade.
Mind-altering medication is by definition prescribed to patients whose cognition and/or moods are in some way impaired. The corollary is that the recipients may not recognise subsequent changes in their thoughts/feelings, because one's internal viewpoint is subjective and adapts to changes, particularly slow ones.
Finally, if mind-altering medications didn't generally have any effect, there would not be widespread use of them for non-medical purposes. {The poster formerly known as 87.81.230.185} 94.12.80.28 (talk) 16:20, 22 March 2017 (UTC)
• Think what the OP would benefit from, is a broader and independent view of the subject than that which we can ever hope to give here. Was most impressed by Robert Whitaker's book Mad in America. Recommend it. It has a detailed bibliography too. Not only I but my local medical library has it on their bookshelf. This book created such a stir that there is a website to help people separate the wheat from the chaff when it comes to psychiatric drugs. You can view it here: [1]. There are much older books. One is There's Gold in Them Thar Pills: Inquiry into the Medical Industrial Complex but that is only about the shenanigans that pharmaceutical companies get up to. To my mind the OP would be better of going to the site like MiA that offers some hope and guidance, much of which the proscriber of his medications has not been taught in Med School -because it is not on the curriculum.--Aspro (talk) 16:31, 22 March 2017 (UTC)
Approved medicines are generally believed by a lot of experts to be "safe and effective". That does not, however, imply that every drug will work for every last patient... nor that the drugs will be found entirely satisfactory at producing optimal functional health even by the majority of patients. It only means that in some studies there was a statistical benefit. Nor does it mean that there is no other way by which a patient could obtain the same benefit - even a better way that is not presently approved, for whatever reason.
It is very appropriate to be skeptical, but -- a skeptic must never forget to be skeptical of his skepticism! Nothing, pro or con, is ever above suspicion, not even oneself. Wnt (talk) 00:08, 23 March 2017 (UTC)
Verily. The efficacy of a drug is often numerated as the NNT. Yet, the guidance on psychiatric drugs often lead proscriber down the garden path. They read in their med journals and are informed by drug reps about NNT but are often oblivious to NNH. So despite the evidence before their very eyes they try to increase the dosage even when the drug for a particular patient doesn't work. Hoping for more-is-better. Something which any pharmacist (who are required to study in depth the action of drugs) will tell you is far from scientific.--Aspro (talk) 17:26, 23 March 2017 (UTC)

WHO

Regarding the election of the Director-General of the World Health Organization, there are three nominees for the position (Tedros Adhanom Ghebreyesus, David Nabarro, and Sania Nishtar). Does this mean that one of those three must be elected Director-General? In other words, are those three names the only options on the ballot or only valid choices? 147.126.10.129 (talk) 17:00, 22 March 2017 (UTC)

Very likely. The WHO is part of the United Nations, so any UN-Member can propose a fitting person to fill a position. In case of the WHO its the World Health Assembly then, where every Member can send some delegate to vote. Ofcourse there is certainly some diplomathy behind closed doors between Members and/or Blocks of Members to determine infront who is proposed and what votes that person will get. --Kharon (talk) 19:34, 22 March 2017 (UTC)
Is Diplomathy where they come to an agreement on the numbers? {The poster formerly known as 87.81.230.195} 94.12.80.28 (talk) 06:27, 23 March 2017 (UTC)
No, diplomathy is not teething people who lithp. StuRat (talk) 06:34, 23 March 2017 (UTC)
I have another question—what is the date and time of the vote for Director-General? Many sources indicate it is in May, but I have yet to see any specific date or time. 147.126.10.158 (talk) 22:37, 23 March 2017 (UTC)

Trauma biochemistry

Why is sharp trauma such as a stabbing even to places like the hand so traumatic and deadly? Is it to do with shock more than blood loss? Or are there other biochemical factors involved? 2A02:C7D:B96A:200:44AE:39E3:1F2E:DE5 (talk) 19:59, 22 March 2017 (UTC)

First of all, is it? Andy Dingley (talk) 20:11, 22 March 2017 (UTC)
Getting stabbed in the heart is a lot more likely to be traumatic and deadly than being stabbed in the hand. ←Baseball Bugs What's up, Doc? carrots→ 20:58, 22 March 2017 (UTC)
Isn't that obvious? --Hofhof (talk) 21:47, 22 March 2017 (UTC)
To you and me, but maybe not to the OP. ←Baseball Bugs What's up, Doc? carrots→ 21:59, 22 March 2017 (UTC)
Maybe he takes some expressions too literally. Hofhof (talk) 22:09, 22 March 2017 (UTC)
I don't know what you mean by "so traumatic and deadly." A stabbing to a hand probably won't kill you, if treated properly. But yes, you can die from any wound that gets infected. A deep wound can inject bacteria deep into a tissue, but that does not make a stab to the hand especially deadly.
Stab wound, ballistic trauma and major trauma can get you further on the topic. --Hofhof (talk) 21:47, 22 March 2017 (UTC)
And of course hemorrage, in cases where this is serious enough and not rapidly managed. PaleoNeonate (talk) 22:40, 22 March 2017 (UTC)
But the same thing also happens in the case of blunt trauma to somewhere like the hand with no bleeding. I think I heard that trauma of any kind can release deadly chemicals into the body °or something? 82.132.242.69 (talk) 13:03, 23 March 2017 (UTC)
Rhabdomyolysis. First noted medically after the San Francisco earthquake of 1906, treatments for it were improved massively during the London Blitz.
We hear so much utter nonsense about "alkalinising" the body these days to "detox" it, but this is one condition where it can be (amongst other things) a relevant treatment. Andy Dingley (talk) 13:13, 23 March 2017 (UTC)

Calories

What tastes good is a matter of opinion. The Reference Desk is not for opinions.
The following discussion has been closed. Please do not modify it.

What is the lowest calorie "junk" food that actually tastes good? — Preceding unsigned comment added by 64.183.94.45 (talk) 20:51, 22 March 2017 (UTC)

Define "junk" food. ←Baseball Bugs What's up, Doc? carrots→ 20:57, 22 March 2017 (UTC)
Junk food: is a pejorative term for cheap food containing high levels of calories from sugar or fat with little fiber, protein, vitamins or minerals.--Hofhof (talk) 22:01, 22 March 2017 (UTC)
Or, perhaps even harder, define "tastes good" (de gustibus non est disputandum, after all). This seems like something where WP:OR at your local food market is the only real solution. — Lomn 21:39, 22 March 2017 (UTC)
Indeed. I recall a song called "The Junk Food Junkie" in which the Hostess Twinkie was the archetype of junk food. Yet I'm sure there are some (or many) who don't like the taste of them. ←Baseball Bugs What's up, Doc? carrots→ 22:03, 22 March 2017 (UTC)
I'd say chewing gum + diet Coke, McDonald's McNuggets and chicken is said to have less calories than others. The Ultimate Chicken Grill Sandwich or Grilled Chicken Go Wrap of Wendy's might be less caloric than other options. --Hofhof (talk) 22:07, 22 March 2017 (UTC)
I wouldn't consider a grilled chicken sandwich to be junk food, and they also have a fair amount of calories. But sugar-free items with artificial sweeteners are unhealthy, and may have zero calories, so I'd say you are right on track with those. StuRat (talk) 22:15, 22 March 2017 (UTC)

March 23

Two seemingly self-contradictory statements in the chemistry textbook

On the same page:

"We must be careful not to confuse the extent to which an electrolyte dissolves (its solubility) with whether it is strong or weak. For example, CH3COOH is extremely soluble in water but is a weak electrolyte."

"...you need only to remember that water-soluble ionic compounds are strong electrolytes."

Acetic acid is a water-soluble ionic compound, no? 69.22.242.15 (talk) 02:22, 23 March 2017 (UTC)

It is not ionic. It is a molecule which only dissociates in water to a small extent. Pure acetic acid (insofar as it can be isolated, which is tricky as hell) has a melting point of 16-17 degrees C. There is no ionic compound with such a low melting point. --Jayron32 03:07, 23 March 2017 (UTC)
Ethylammonium nitrate is an ionic compound, and its melting point is 12 °C. 1-Butyl-3-methylimidazolium tetrafluoroborate is about –80 °C. See ionic liquid:) DMacks (talk) 03:19, 23 March 2017 (UTC)
Yes, but obviously the OP isn't helped in their understanding of chemistry by bringing up oddities and exotic examples. At the level of misunderstanding they are having, bringing up such things, while true, is likely to confuse them more. Pedagogy involves more than espousing randomly true statements. If learning were that easy, the internet would already suffice and we'd all know everything already. Please don't confuse the OP further. At their level of understanding, they need to know that acetic acid is a molecular compound, and that ionic compounds can generally be expected to be high-melting solids. They can have fun with the oddities later in life. --Jayron32 03:44, 23 March 2017 (UTC)
If you must bring up such things, I would imagine that you should also qualify it with some sort of rationalisation that is understandable at that level, such as "in this case, the cation and anion are very asymmetrical and don't pack well; most cases are not like that". Double sharp (talk) 03:52, 23 March 2017 (UTC)
Is you them or is you me? Or is you someone else? --Jayron32 03:54, 23 March 2017 (UTC)
DMacks. Sorry for the lack of clarity there. Double sharp (talk) 03:59, 23 March 2017 (UTC)
It's certainly important to teach generalities early, but I think it's also important not to teach them as absolute rules. DS is right, in that I usually use words like "generally" and "in most cases" when stating these patterns in this context. It helps minimize the need to lie to children as blatantly about patterns that even at an introductory level become just narrowly scoped parts of larger patterns. Even intro-chem textbooks talk about symmetry and packing to discuss trends of physical properties not strictly boolean, and that ionic vs covalent is a continuum. Otherwise my students have learned a strict fact like "ionic substances are soluble in water" and then a few weeks later it's contradicted by "silver halides are not soluble in water". I'm not sure if they eventually become numbed by a pile of loose facts "for this exam" and then brain-purge for next time or just don't care to integrate their knowlege, but either way, they seem to do better in later classes if at least there was a seed that things are not "either/or" and that there is more going on than we can teach right away. DMacks (talk) 15:04, 23 March 2017 (UTC)
To build on what others have said, acetic acid's solubility in water isn't deriving from a dissociation into ions. In a 0.1M solution of acetic acid, only about 1.3% of the acid molecules will have dissociated into hydronium and acetate ions, the rest will still be CH3COOH. Despite that fact that 98.7% of the molecules didn't dissociate, ~100% of the molecules are dissolved in water in that solution, so there must be some other mechanism for the solubility than just ionic dissociation. What might that be? Well, the carboxylic acid end of the molecule has a great proton donor and proton acceptor for hydrogen bonding, which is great for solubility in water. This is one of the reasons why being strongly soluble may not have anything to do with being a strong electrolyte; there are other solubility mechanisms. --OuroborosCobra (talk) 12:23, 23 March 2017 (UTC)

Torque, Moment of inertia

I'm trying to get the rigid body science. It's even tougher for me than regular classical mechanics - and you could guess how long I had to work on that.

As I understand, in classical mechanics the only things we get "a priori" are velocity and acceleration. Other stuff, force for example, we tend to measure experimentally by using springs etc, and then get mass. That's how we derive ${\displaystyle {\vec {F}}=m{\vec {a}}}$ .

What I'm trying to find is if similar experiments were done in rigid body science. Angular acceleration I can understand "a priori", but what about the others? Had people measured moment of inertia by connecting a spring to a lever, applying constants forces on it, defining them as torque and measuring the angular accelerations?

Is That how we derive ${\displaystyle {\vec {\tau }}=I{\vec {\alpha }}}$ ? יהודה שמחה ולדמן (talk) 09:29, 23 March 2017 (UTC)

It wasn't really done experimentally for force, and once you have defined F=m.a then T=omega_dot.I can be worked out analytically. Greglocock (talk) 09:52, 23 March 2017 (UTC)
But am I in the right direction? There are scientific things that at first were actually thought experiments, like understanding inertia by minimizing friction - and this was confirmed in physical experiments and also in outer space.
Is the torque—spring experiment above doable? יהודה שמחה ולדמן (talk) 10:14, 23 March 2017 (UTC)
Torsion spring might be of interest to you. Otherwise, your "a priori" vs. "experimentally" distinction (BTW, the technical term, coined by Kant, is the a priori and a posteriori distinction) seems fairly muddled. Position, velocity, etc. are no more pure platonic ideas than force, charge, mass. You need experimental checks to know a speed/acceleration. TigraanClick here to contact me 12:12, 23 March 2017 (UTC)
• If they had looked at moments of inertia, it would almost certainly be from trying to invent new sorts of escapement for clocks and timepieces. In particular, look at verge. It was understood how to adjust the foliot of these by moving two masses in and out, adjusting the moment of inertia. Andy Dingley (talk) 13:10, 23 March 2017 (UTC)
How did people derive the definition of torque as ${\displaystyle \tau =r\cdot F\cdot \sin(\theta )}$ ? How did they understand that this product is all they need? Yes, I know about the lever — is this how we know that the force applied on the lever is ${\displaystyle F_{\perp }\propto {\frac {1}{r}}}$ ? יהודה שמחה ולדמן (talk) 13:36, 23 March 2017 (UTC)
Torque was first understood from the static case, for levers in balance, long before it was considered for continuous rotation. Also the idea of ${\displaystyle \sin(\theta )}$ only really comes in once you move away from gravity on a horizontal beam.
What's interesting though (and I'd never considered before) is that the moment of inertia of a foliot was being understood enough to be practically used in the 14th century, three hundred years before Newton is considering linear inertia. I guess that the absence of air resistance and its effect as a confusing factor (see impetus) would have helped. Andy Dingley (talk) 13:49, 23 March 2017 (UTC)
Newton's great innovation was not the discovery of kinematics: his contribution was a specific mathematical method (the calculus of derivatives) that accurately modeled elementary kinematics as second-order linear equations. If you study the history of physics, you'll find plenty of examples of earlier great thinkers who were nearly correct. The simplified narrative suggests that everyone used Aristotelian physics until one day the proverbial apple fell... but that's a bit of an abridged version of the history of science! As the first example that comes to my mind - Kepler's equation of planetary motion invokes the inertia of a revolving body quantitatively - it's just less generalized than Newton's models for kinematics and gravity. But if we're holding physicists to the arbitrary standard that their equations need to be even more generalized, Newton's model falls short as well... Nimur (talk) 14:13, 23 March 2017 (UTC)
How could you not quote "standing on the shoulders of giants" when the example involves Newton not discovering mechanics from scratch... TigraanClick here to contact me 14:39, 23 March 2017 (UTC)
Because Newton was a git. Andy Dingley (talk) 16:22, 23 March 2017 (UTC)

Why wasn't the torque defined as a scalar, like work and energy? If work as a scalar can be positive\negative, so can torque etc. יהודה שמחה ולדמן (talk) 22:37, 23 March 2017 (UTC)

Obviously torque has a direction too. Andy Dingley (talk) 23:14, 23 March 2017 (UTC)
Why? What is the point of using pseudovectors? When we talk about work, we could refer to it being directional by ${\displaystyle W=|{\vec {F}}|\cdot |{\vec {x}}|\cdot \cos(\theta )}$ . And we still call that a scalar.
Maybe torque can be defined to be a circular vector. יהודה שמחה ולדמן (talk) 23:56, 23 March 2017 (UTC)
Read some of Feynman, such as his explanation of gyroscopic precession. As usual, he's wonderfully clear on it - because he picks the right frame of reference: one that relies on the representation of torque as a vector like this. Andy Dingley (talk) 00:13, 24 March 2017 (UTC)
Sorry, I had my own Eureka! moment about the Gyroscope a few months ago after many years reading the same damn useless "crap" (pardon me) of angular momentum and torque.
At the end, I didn't need to understand any of these — it finally hit me when I understood that the force applied perpendicular to a rotating wheel's plane behaved just like the centripetal force in a circular motion.
But if you could show me pages or videos of Feynman I might learn something more. יהודה שמחה ולדמן (talk) 00:40, 24 March 2017 (UTC)
Web search, there's lots out there. His very short book on a graphical demonstration of Newtonian orbital mechanics, rather than calculus, is very good demonstration of the sort of "other ways of looking at things" approach that he was so good at.
The 'Lectures' are here: http://www.feynmanlectures.caltech.edu/
Andy Dingley (talk) 01:42, 24 March 2017 (UTC)
Torque only became a focus after Strength of materials became important. Today its mainly used in the field of construction and design. Its main essence is not well described as kinematics/motion but much better as Elasticity (physics). --Kharon (talk) 02:47, 25 March 2017 (UTC)

How accurate is this table? (March 17)

Re this exchange:

Even more awesome is the Zoroastrian calendar:

365, 365, 365, 365.
Repeat forever.
Repeats four times sooner than the Julian, 400 times sooner than the Gregorian and 900 times sooner than the Revised Julian. 86.128.233.163 (talk) 22:55, 19 March 2017 (UTC)
And eventually you get to "June in January". ←Baseball Bugs What's up, Doc? carrots→ 00:02, 20 March 2017 (UTC)
But we already have the opposite seasons in the Southern Hemisphere, so avoiding our seasons slowly drifting isn't necessarily worth all the trouble of leap years (although admittedly they aren't as much trouble as Daylight Savings Time, requiring 2 clock adjustments per year). StuRat (talk) 16:12, 23 March 2017 (UTC)
Nobody has mentioned the Revised Gregorian calendar, which is guaranteed to be 100% accurate forever. See Talk:Tropical year/Archive 3#Source updated and read the seven paragraphs above the section header. This really shouldn't be a redlink - there's more than enough information there to start an article. 86.128.233.163 (talk) 23:24, 20 March 2017 (UTC)
I've created an article at Draft:Revised Gregorian calendar. If someone can review it and transfer it to mainspace that would be appreciated. 86.128.233.163 (talk) 12:12, 21 March 2017 (UTC)

There are some more fictional calendars not mentioned by Sagittarian Milky Way, described at [2] and [3]. Are there any others in books/games/TV series etc.? 86.170.156.155 (talk) 15:41, 23 March 2017 (UTC)

I really don't see the point of the so-called Revised Gregorian calendar since there are so many variables that cannot be predicted this far in advance. The existing Gregorian calendar will suffice for the next thousand years, by which time we might be able to make more accurate predictions of future day (and year) lengths. We already have Sir John Herschel's suggested revision in the article Gregorian calendar so we could mention any other well-referenced suggested improvements there. Dbfirs 17:51, 23 March 2017 (UTC)
Then you probably don't see the point of the 4-4-5 calendar, Armelin's calendar, Discordian calendar, Dreamspell, Hanke-Henry Permanent Calendar, International Fixed Calendar, Invariable calendar, Middle-earth calendar, Pax calendar, Positivist calendar, Stardate, Symmetry454, Tranquility calendar and the World calendar, all of which have articles.
I agree the Gregorian calendar article needs updating, but the problem is it's protected. The needed corrections would appear to be as follows:
• Second paragraph: replace the second sentence with

The motivation for the reform was to stop the drift of the calendar with respect to the equinoxes and solstices. The Church became involved because Easter was traditionally observed in the third week of the lunar month next after the spring equinox but the tables in use were causing it to drift away from both the equinox and the period between full moon and last quarter.

• "Gregorian reform" section: replace "Because the spring equinox was tied to the date of Easter" with "Because Easter was tied to the date of the spring equinox."
• In the "Accuracy" section delete the second paragraph. At the end of the third paragraph add:

Historical proposals for improving the Gregorian calendar have not taken account of this fact. Following the successful introduction of the leap second regime a modification has been proposed which will ensure it remains 100 per cent accurate forever.[Link to article]

carbohydrates

When it comes to dieting carbohydrates are the devil.

If a person only eats 800 calories of potatoes that are mostly carbohydrates, will they lose weight? Will it be slower than eating 800 calories of non-carbohydrates? — Preceding unsigned comment added by 168.10.85.15 (talk) 19:22, 23 March 2017 (UTC)

Before we get into this, define what you mean by dieting. Do you mean it in the true sense of 'diet' or the self-imposed restriction of food? --Aspro (talk) 19:34, 23 March 2017 (UTC)
Carbohydrates can also be good - see Why are Carbohydrates Important for Athletes?. Alansplodge (talk) 19:42, 23 March 2017 (UTC)
If you eat any kind of macronutrient more than what your body can metabolize, then you will gain weight in fat. See this image for details. I would just eat a hearty meal before some kind of vigorous physical activity. 140.254.70.33 (talk) 19:46, 23 March 2017 (UTC)

Whole grain carbs are good, the human body has evolved to use such carbs for almost all of its energy needs. Fat intake should be limited to less than about 15% of the total energy intake, the bulk of this should come from fats that are present in whole foods, like walnuts, chia seeds etc., not from cooking oil, even olive oil will damage the cardiovascular system (studies that show that extra virgin olive oil is healthy are flawed because they compare using this healthier oil to saturated fats, that's like comparing smoking cigars to light cigarettes with a filter and concluding that smoking such cigarettes is good for lung health) it also causes type 2 diabetes. If you get most of your energy from carbs, you'll find it a lot easier to exercise hard, you may then be able to lose weight while retaining your fitness level.
I actually lost weight while increasing my energy intake to close to 4000 Kcal per day several years ago (I used to weight about 63 kg, I now weight about 55 kg). This is because I eat a very low fat diet and I exercise hard every day (one hour of fast running, this burns more than 1000 Kcal). So, a low fat diet allows you to eat as much as you like, it enables your own body to regulate the metabolic rate to get to its ideal weight. Count Iblis (talk) 20:08, 23 March 2017 (UTC)
Since this is the Reference Desk, can you provide references for any of your claims? --47.138.161.183 (talk) 00:29, 24 March 2017 (UTC)
I posted a more detail reply with more refs here. Count Iblis (talk) 02:06, 24 March 2017 (UTC)
Eating 800 food calories a day without medical supervision is a good way to kill yourself, doubly so if it's just one food, which will inevitably lead to micronutrient deficiencies. Such dramatically low-calorie diets are sometimes used, but only under supervision. Besides that, there appears not to be scientific consensus on whether a low-carbohydrate diet or high-carbohydrate diet is best for weight loss. It's quite possible the answer varies among people. "Carbohydrates are the devil" does not seem to be a widely-held belief in the scientific community. --47.138.161.183 (talk) 00:29, 24 March 2017 (UTC)
OP, your question is not clear. The first question only has one dependent clause, and the main clause is a question. Such a question is impossible to answer, because not enough details are given. Are the 800 kcal of potatoes the only food the person is eating, or are the 800 kcal of potatoes part of a wholesome diet? What kind of potatoes are they? Obviously, potatoes must be cooked, or they will poison the human consumer! What is the person's activity level? How much energy does that person need to consume to stay alive? Your second question is equally unclear. What do you mean by "slow"? Are you referring to the rate at which each macronutrient is consumed in isolation? How would we know? 50.4.236.254 (talk) 01:46, 24 March 2017 (UTC)
Glycemic index may be of interest. PaleoNeonate (talk) 02:49, 24 March 2017 (UTC)

Let's have a look at the actual science. The fact is that, regardless of what people believe, a high-carbohydrate diet is incompatible with our Paleolithic genome. It causes epidemics of obesity, hypertension, diabetes, and atherosclerotic cardiovascular disease. Out diet should be consistent with our hunter-gatherer genetic legacy. [4] --IEditEncyclopedia (talk) 05:38, 25 March 2017 (UTC)

The Case Against Sugar is a book which gives a detained outline of the misguided dietary beliefs. --IEditEncyclopedia (talk) 05:38, 25 March 2017 (UTC)

Sugar industry paid scientists to blame fat [5][6] --IEditEncyclopedia (talk) 11:18, 25 March 2017 (UTC)

One more reference [7]. --IEditEncyclopedia (talk) 11:26, 25 March 2017 (UTC)
"Carbohydrate" and "sugar" are not equivalent. The first review you linked says people should eat lots of fruits and vegetables, which are mostly carbohydrates. I doubt you will find any authority that disagrees that you should minimize added sugar intake. This is not the same thing as "don't eat carbohydrates". --47.138.161.183 (talk) 23:23, 25 March 2017 (UTC)

Running like Forrest Gump

If a person begins running to the next-door neighbor on the first day, stops, turns back, runs to the end of the street on the second day, stops, turns back, then will this person get stronger and faster at running by the end of the year? What kind of animal will the person be able to outrun? Will the person be able to outrun a horse? If one cannot outrun the horse by speed, then can one outrun the horse by endurance or passing of time? 140.254.70.33 (talk) 20:21, 23 March 2017 (UTC)

Persistence hunting is a thing - people in very good aerobic condition can outrun a horse, in the long run. Now as to whether this movie Forrest Gump can be interpreted as a conceivable method of endurance training, that's another question. Wnt (talk) 20:30, 23 March 2017 (UTC)
The article endurance training has a little section about the negative effects of long-term, excessive endurance training. I wonder how long that may be. 140.254.70.33 (talk) 20:40, 23 March 2017 (UTC)
• My father once told me that you could always catch a rabbit if you kept chasing it in the open until it gave up. I was in an oak wood on hills with an understory of mountain laurel, and saw a rabbit. It kept dodging from shrub to shrub, but could not escape my sight. After about 5 minutes it stopped running and I caught it by the nape of the neck. I brought it home, wrapped in my jacket to calm it, and showed my dad, then let it go free. (At the time that wood abutted our back yard.) μηδείς (talk) 22:59, 23 March 2017 (UTC)
Sounds to me like the story of Milo of Croton who got strong by lifting up a calf every day while it grew to be a bull. Dmcq (talk) 23:26, 23 March 2017 (UTC)
There's a famous story about Louis Leakey outrunning game animals like antelopes, think I read about it in an ancient National Geographic. A quick google finds Carl Sagan commenting that he liked to do it naked and this book co-edited by Leakey's son. Should probably be in his or the persistence hunting article.John Z (talk) 01:06, 24 March 2017 (UTC)
The annual Man versus Horse Marathon is generally won by a horse, but occasionally by a person. MChesterMC (talk) 09:03, 24 March 2017 (UTC)

Subsistence farming

If a subsistence farmer grows food in a temperate, coniferous region, and the season is marked by extreme weathers (long winters and dry, scorching summers), then can one depend on the pine nuts of the conifers for survival, until nature slowly consumes the person's life due to nutritional deficiencies? Can plants live off of indoor lighting? Does the lightbulb type matter? Do plants have an ideal comfy temperature? Will talking to plants and singing to plants bring more yield? 50.4.236.254 (talk) 22:29, 23 March 2017 (UTC)

Do you mean vampiric pine nuts, or zombiacal pine nuts? μηδείς (talk) 23:01, 23 March 2017 (UTC)
A diet of pure pine nuts would be fairly rich, but missing vitamin A and be very low in vitamin C, so your hypothetical person would likely be facing scurvy, blindness, and a weakened immune system. This would greatly increase his chance of dying from illness or injury, but probably won't kill directly. For indoor plant growth, you might want to read grow light. Your typical house lighting is not very bright compared to the sun, so specialized lights are used instead. And yes, plants do have ideal temperature ranges, outside of which they don't grow as well, and far outside of which they don't grow at all. For your final question, I have no idea where you got that idea. Someguy1221 (talk) 23:05, 23 March 2017 (UTC)
If that's true, the cure for one problem is not far away: pine needle tea has famously been used as a cure for scurvy (Jacques Cartier being an example). [8] I see our article also says it's a source of vitamin A (which I hadn't been expecting). ERmm -- an issue I see with the not very confidence inspiring source I saw the claim in is that the Cartier article says Aneda wasn't pine needles, but a different evergreen tree. Wnt (talk) 00:21, 24 March 2017 (UTC)
Adding dandelion greens to the diet can prevent vitamin A deficiency. With a diet of pine nuts, pine needles, and dandelion greens, one nutrient that will be lacking is vitamin B12, but that can last a long time. I wonder if you can get vitamin B12 from the occasional mealworm. 50.4.236.254 (talk) 00:33, 24 March 2017 (UTC)
The gents at Mythbusters examined the singing to plants item and concluded that it was plausible, as the plants not spoken to did the most poorly among the test subjects. More interesting bits here at the BBC. Matt Deres (talk) 01:30, 24 March 2017 (UTC)
Plants you sing to might be getting more of your CO2 and thus doing better than the ones that don't. ←Baseball Bugs What's up, Doc? carrots→ 05:47, 24 March 2017 (UTC)
Well, maybe. But there seems to be evidence (See mythbusters link above, and many many others) that recordings of voice or music seem to aid plant growth through some unknown mechanism. ApLundell (talk) 14:26, 24 March 2017 (UTC)
Then the question becomes, what kind of music? Like if you played Florence Jenkins, would it cause cell membranes to rupture? ←Baseball Bugs What's up, Doc? carrots→ 14:41, 24 March 2017 (UTC)
That's not farming, that's gathering.
Sleigh (talk) 05:42, 24 March 2017 (UTC)
Maybe unless you planted them. ←Baseball Bugs What's up, Doc? carrots→ 14:41, 24 March 2017 (UTC)
You might be surprised at how fast you run out of easy food. The per-person land requirements for hunter-gatherers are surprisingly large[9] even in good conditions, which presumably you're not in if you're thinking about exclusively eating pine nuts.
There's a reason most hunter-gatherers were nomadic. They had to keep moving to fresh land. ApLundell (talk) 14:33, 24 March 2017 (UTC)

March 24

To disinfect with alcohol or not after a bite from dog?

I've listen to lecture today where the professor said that it's forbidden to disinfect the location of the bite with alcohol (in case of suspicion for rabies). As for the reason he wasn't really clear. Moreover, by googling I found that in the site health minstry of Israel they recommend to disinfect with alcohol. What's going on here? Apparently one of them is not right. 93.126.88.30 (talk) 04:24, 24 March 2017 (UTC)

The WHO and other sources [10] [11] [12] recommend thorough washing and flushing (10-15 minutes) with soap and water immediately and before any cleaning/disinfecting with alcohol. If no soap is available just use water. Nil Einne (talk) 04:38, 24 March 2017 (UTC)
Forbidden? There is no legal legistration any where in the world where it is legally forbidden to clean a wound with alcohol. Perhaps the professor is refering to Islam where it is forbidden to consume alcohol but even then consume means to drink and it does not mean you cannot use alcohol for medical disinfectant purposes. Look at this link [[13]]. No wonder your professor thinks that alcohol is the most evil "thing" in the world, where even touching or smelling a little bit of alcohol is enough to turn you into the spawn of satan. 148.182.26.69 (talk) 04:59, 24 March 2017 (UTC)
That would also be ignorance on their part, as rubbing alcohol is basically a poison which is not intended to be consumed by mouth. ←Baseball Bugs What's up, Doc? carrots→ 05:44, 24 March 2017 (UTC)
Given that the OP is in the Ukraine the use of "forbidden" is probably due to English not being their first language. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 00:08, 25 March 2017 (UTC)
Your best bet is to call your doctor (before you get bitten) and ask how to treat a dog bite. ←Baseball Bugs What's up, Doc? carrots→ 05:44, 24 March 2017 (UTC)
"Doc, I plan to taunt the neighbor's pit bull then jump over the barbed wire fence, into his yard. How should I treat the bites, if I survive ?" StuRat (talk) 06:38, 24 March 2017 (UTC)
Or, "Doc/nurse/receptionist, I'm curious whether a dog bite can or should be treated with rubbing alcohol?" "Have you been bitten?" "No, but there's vicious-looking Chihuahua living nextdoor, and I want to be proactive." ←Baseball Bugs What's up, Doc? carrots→ 08:35, 24 March 2017 (UTC)
"Wear long pants and buy a cat". Count Iblis (talk) 23:01, 24 March 2017 (UTC)
The general medical advice is not to use alcohol or other antiseptics to clean open wounds, as they can actually cause more damage to the tissue. The NHS website - http://www.nhs.uk/chq/Pages/1054.aspx?CategoryID=72& - says to use cold water, saline solution, or a non-alcohol wipe. If you are dealing with someone else's wound, then you might use a bit of alcohol to sterilise your own hands before touching the wound. Wymspen (talk) 11:56, 24 March 2017 (UTC)
Exactly. And as far as rabies is concerned alcohol has little effect on most viruses. Just do what is said there, the bleeding while you're washing it out gives a far better chance of getting rid of anything - a dog's mouth isn't a very clean place at the best of times. Dmcq (talk) 12:15, 24 March 2017 (UTC)
That depends on the virus, doesn't it? I have the notion that viruses dependent on a viral envelope can be killed ("inactivated" if you prefer; I don't) by alcohol. Specifically that's supposed to be why hand sanitizers are useful in limiting the spread of influenza. I think. Let me know if I have that wrong. --Trovatore (talk) 20:57, 24 March 2017 (UTC)
Sorry yes you're right and rabies is enveloped - however I see that even though isopropyl alcohol can kill rabies ethanol isn't very effective - since hand sanitizers can use either or something else one can't depend on them. The WHO advice is best. Dmcq (talk) 23:13, 24 March 2017 (UTC)
Interesting. Any idea why they would be different? --Trovatore (talk) 23:45, 24 March 2017 (UTC)
Right, although isopropyl alcohol being much more toxic, is not recommended to put directly in contact with large wounds (also inadequate for mouth rinse). It also has other properties, it can even be used to wash off glue residues and various types of persistent inks, which ethanol is not particularily good for... PaleoNeonate (talk) 00:57, 25 March 2017 (UTC)
Is it "much more toxic"? I mean, it is orally, sure — causes "gastric distress" as it says on the label. But on a wound? I'd never heard that. Do you have a link? --Trovatore (talk) 01:21, 25 March 2017 (UTC)
I'd have to search from isopropyl alcohol myself probably; however I have a bottle here with 70% content and warning to not put in contact with mucous membranes. PaleoNeonate (talk) 01:26, 25 March 2017 (UTC)
You don't want to be putting 140-proof grain alcohol on too many mucous membranes either. --Trovatore (talk)
Hmm so unless those tables are wrong, ethanol would have an LD50 (oral, rat) of 7060 mg/kg and isopropanol would have an LD50 (oral, rat) of 5045 mg/kg. Although this shows that it is more toxic, it's not as different as I had anticipated, and of course there are other factors, metabolization being complex... [14], [15], Median_lethal_dose. PaleoNeonate (talk) 02:05, 25 March 2017 (UTC)
And the best part is that to treat wood alcohol poisoning, giving the patient grain alcohol works in a pinch. One of the toxic metabolites of isopropanol is rate limited and the presence of ethanol slows the production of the toxic chemical. Giving them a beer can mean the difference between blindness and sight. --DHeyward (talk) 03:28, 25 March 2017 (UTC)
Right idea, wrong alcohol. Wood alcohol is actually methanol; that's the one that makes you go blind. Isopropanol mostly gives you a tummy upset, I think.
Methanol gets metabolized to two nasty substances, formaldehyde and formic acid. I'm not sure what happens to isopropanol, but if it follows the same pathway, it seems like it should turn into acetone, which isn't that bad (it's part of some normal metabolic pathways anyway). --Trovatore (talk) 04:44, 25 March 2017 (UTC)
Actually maybe DHeyward meant to type "methanol" but typed "isopropanol" by mistake because it was under discussion. That would make the comment make perfect sense. --Trovatore (talk) 20:33, 25 March 2017 (UTC)
I see Rabies#Treatment says basically the same thing as the WHO above. Alcohol or iodine is used at the end as it may clear up some remaining virus. Dmcq (talk) 12:24, 24 March 2017 (UTC)
Alcohol or iodine can still be used to disinfect the intact skin around the wound to prevent a secondary infection. Ruslik_Zero 20:43, 24 March 2017 (UTC)

01:32, 25 March 2017 (UTC)

Disinfect is overrated. Dog bites hurt and that is a two shot minimum. Wait 30 minutes and if there is still pain, throwback another 2 shot. Continue until pain is resolved. --DHeyward (talk) 21:11, 24 March 2017 (UTC)
That might be characterized as giving "medicinal" advice. ←Baseball Bugs What's up, Doc? carrots→ 22:00, 24 March 2017 (UTC)
"Old Medicine, it's down right barbaric! Dialisis, Chemotherapy, drillin' holes in peoples heads, it's like the Goddamn Spanish Inquisition!" PaleoNeonate (talk) 01:02, 25 March 2017 (UTC)
Friends, thank you for your comments. I would like to add that the professor is not Muslim but he is Christian, anyway he's not against alcohol as someone said here. If I understood him correctly then he said that when alcohol is applied on the place of the bite, then the alcohol has an effect of immunosuppression and interrupt to kill the viruses. But I'd not think that he's the best professor to study from him. I found already some mistakes in his things in the past and that's why I came here to ask. 93.126.88.30 (talk) 02:15, 25 March 2017 (UTC)
Madstones were at one time advocated in suspected cases of bites by a mad dog, before Pasteur developed the rabies vaccine which actually works. Edison (talk) 02:18, 25 March 2017 (UTC)
Apparently no one linked our animal bite article. See the "Treatment" section. Note that antibiotics are recommended for dog and cat bites of the hand, and possibly other bites if there is a high risk of infection. Also tetanus prophylaxis may be indicated. You should see a medical professional for anything more than a superficial bite. As some of the above replies have noted, the general advice for non-major wounds has shifted towards just cleaning with soap and water. Antiseptics like alcohol don't appear to be any better, and may cause more complications. --47.138.161.183 (talk) 23:41, 25 March 2017 (UTC)
The use of alcohol as a disinfectant is not not necessarily forbidden in Islam "the Muslim Judicial Council of South Africa has issued written permission regarding the use of alcohol not produced as a result of fermentation for the specific purpose of disinfecting the hands. In addition, due various health concerns during Hajj (religious pilgrimages to Mecca and Medina), in 2002 the World Muslim League in Mecca issued a fatwa allowing the use of alcohol based hand sanitizers. During this year’s Hajj, Saudi Deputy Health Minister Dr. Ziad Memish reiterated that Saudi senior religious leaders deem alcohol-based sanitizers acceptable" [16]. Richerman (talk) 00:15, 26 March 2017 (UTC)

WHO

What is the date and time of the vote for Director-General of the World Health Organization? Many sources indicate it is in May, but I have yet to see any specific date or time. 147.126.10.21 (talk) 23:41, 24 March 2017 (UTC)

March 25

Why can't humans hibernate?

Winter seems to be the worst time to grow food. It's too cold and snowy. Why can't humans hibernate during the winter and feast on as much food as possible during other seasons like squirrels? 50.4.236.254 (talk) 01:38, 25 March 2017 (UTC)

There is some material near the bottom of this page. Matt Deres (talk) 02:03, 25 March 2017 (UTC)
[Edit Conflict] Because humans evolved in Africa, quite recently in evolutionary terms, where there was no 'winter' corresponding to your description, and where in any case they did not grow food, being hunter-gatherers.
After spreading out from Africa, they did not live long enough in latitudes with significant winter seasons to evolve hibernation before their burgeoning intelligence and culturally preserved learning enabled them to combat winter conditions by other means (for example clothing, use of fire, shelters, seasonal migration); some of them also evolved physically to withstand colder climates better. Once agriculture was invented, they became more tied to remaining in one place, but also learned to stockpile food to sustain them over the winter.
Hibernation has drawbacks as well as advantages, in that hibernating individuals may be very vunerable to predation – if you're rare, large and/or fierce when awakened, or well hidden like squirrels your species can survive, but humans became too numerous and to findable by intelligent predators in the shape of other humans for this ever to be viable. {The poster formerly known as 87.81.230.195} 94.12.80.28 (talk) 02:07, 25 March 2017 (UTC)
At Hypothermia#Signs_and_symptoms there is mention of a few states some of which are also associated with hibernation. But indeed we're not adapted for it. Also, other than predation, even for hibernating animals, there is an increased risk of death, they still must face a type of shock. Unfortunately I didn't find information about this latter part in the current hibernation article with a quick look. But I remember that some domestic animals which can hibernate in natural conditions can also enter stupor torpor if the temperature is slightly too low. Sometimes they don't recover. PaleoNeonate (talk) 10:10, 25 March 2017 (UTC)
When you cite squirrels, I assume you mean members of the ground squirrels such as groundhogs because most tree squirrels don't hibernate. (There might be exceptions?) Dbfirs 12:02, 25 March 2017 (UTC)
I had the same question. Chipmunks and woodchucks are closely related and hibernate, but I see more squirrels in the winter than I do in the summer. μηδείς (talk) 15:43, 25 March 2017 (UTC)
Tree squirrels behave like many of us humans in that, when the weather is particularly bad, they stay warm and dry in their dray and perhaps eat some of their stored food, but that isn't hibernation or even torpor. Dbfirs 16:51, 25 March 2017 (UTC)
Humans react badly to disruption of their 24-hour Circadian rhythm that is controlled by a Circadian clock within the suprachiasmatic nucleus (SCN), a bilateral nerve cluster of about 20,000 neurons in the hypothalamus.Experiments have found that normal people cannot entrain even to a longer 28-hour day and prolonged Circadian rhythm sleep disorders are associated with harmful psychological and functional difficulties. An Induced coma such as doctors may induce using a Barbiturate e.g. during major Neurosurgery or when treating rabies cannot be compared with a Hibernation and may result in cognitive impairment after recovery. Animal Dormancy is not well understood, particularly what triggers their Hibernation, or brumation the comparable reflex in Reptiles, but it can be noted that some are obligate hibernators and others are facultative hibernators i.e. they hibernate only when cold stressed or food deprived. Suspended animation of humans is at present a subject of speculation, experiment and fiction. Blooteuth (talk) 17:16, 25 March 2017 (UTC)
Evolution is a random process and different species survive by evolving different strategies for survival. As an example, the Polar bear and the Arctic fox both live in Arctic but Polar bears hibernate and Actic foxes don't, so even if humans had originally evolved in a cold climate they wouldn't necessarily have evolved into a species that hibernates. Richerman (talk) 00:35, 26 March 2017 (UTC)

Why does the medical establishment blame fat?

Agenda-pushing. ←Baseball Bugs What's up, Doc? carrots→ 14:21, 26 March 2017 (UTC)
The following discussion has been closed. Please do not modify it.

Let's have a look at the actual science. The fact is that, regardless of people's belief, a high-carbohydrate diet is incompatible with our Paleolithic genome. It causes epidemics of obesity, hypertension, diabetes, and atherosclerotic cardiovascular disease. Out diet should be consistent with our hunter-gatherer genetic legacy. [17]

The Case Against Sugar is a book which gives a detained outline of the misguided dietary beliefs. Sugar industry paid scientists to blame fat [18][19] [20].

Despite all these, why does the medical establishment blame fat? --IEditEncyclopedia (talk) 12:10, 25 March 2017 (UTC)

Blame fat for what? ←Baseball Bugs What's up, Doc? carrots→ 12:59, 25 March 2017 (UTC)
Illness. --IEditEncyclopedia (talk) 13:14, 25 March 2017 (UTC)
What illness? ←Baseball Bugs What's up, Doc? carrots→ 13:19, 25 March 2017 (UTC)
This seems to be a statement about Paleolithic diet more than a clear question. But yes, nutritionists are still divided on a number of issues. PaleoNeonate (talk) 13:34, 25 March 2017 (UTC)
No, it is not about paleolithic diet, it is about the fallacy that eating fat makes one fat. --IEditEncyclopedia (talk) 13:55, 25 March 2017 (UTC)
Next thing you'll be telling us is that eating fat doesn't clog up your arteries. ←Baseball Bugs What's up, Doc? carrots→ 14:10, 25 March 2017 (UTC)
A reference: "Any fat not used by your body’s cells or to create energy is converted into body fat. Likewise, unused carbohydrate and protein are also converted into body fat... Too much fat in your diet, especially saturated fats, can raise your cholesterol, which increases the risk of heart disease". National Health Service - Fat: the facts. Alansplodge (talk) 14:39, 25 March 2017 (UTC)
Add to this that fat has loads of calories per weight unit. Sugar does not lack far behind. Eating 100 g adds 387 calories to your diet in the case of sugar, and 541 in the case of fat. Hofhof (talk) 14:52, 25 March 2017 (UTC)
So you formed a opinion based on reading one pop science book, and your question is why doesn't the entire medical establishment share that opinion? ApLundell (talk) 15:16, 25 March 2017 (UTC)
don't use labels like "pop science book" to judge, look for logic. And you should be aware of a logical fallacy called argument from authority. --IEditEncyclopedia (talk) 05:19, 26 March 2017 (UTC)
And there's a big dubious supposition in the need of a citation needed tag: "why does the medical establishment blame fat." Does it blame fat? Hofhof (talk) 16:05, 25 March 2017 (UTC)

"Why did the medical establishment become fat?" PaleoNeonate (talk) 19:01, 25 March 2017 (UTC)

Salt, sugar and fat are poisons that we're addicted to. The salt, sugar and fat industry have made propaganda for more than a century to sell the idea that what they produce is healthy. The medical establishment consist of people who are not immune to indoctrination, it's quite similar to the issue of smoking in the late 19th century when there was evidence that it was harmful. The attitude of the medical establishment at the time was:
"In the mid- to late-19th century, doctors determined that lip and tongue cancer rates were higher among smokers of pipes and cigars. Despite this link, major medical journals mocked those who opposed smoking. The Lancet, the leading journal of the time and still one of the most important medical journals in the world, wrote in 1879, “We have no sympathy with prejudices against … tobacco, used under proper restriction as to the time and amount of the consumption. ... A cigar when the mood and the circumstances are propitious [is] not only to be tolerated, but approved.” Moderation, not abstinence, was the order of the day."
Now, fat is bad because we're using large amounts in refined form, just like sugar is bad when used in that way. And salt is very bad for health too. The human body has evolved to take in about 0.1 grams of salt a day, and sugars and fats from whole foods found in nature, e.g. from fruits and nuts. The reason why refined sugars and fats are bad is that we use a lot more of it than our bodies are designed from and in refined form it enters the body much faster than if you consume the same quantities from whole foods. Also, your body needs a lot of nutrients like vitamins and minerals, refined oils and sugars yield calories without those nutrients. So, we're then at risk of falling short. Now overt shortages casing diseases like scurvy is easily avoided, but we don't know how much we need for optimal health. Heart disease at old age may be considered to be normal, but it could also be that the normal intake of oils and refined sugars leads us to a suboptimal intake of nutrients leading to diseases that would otherwise not occur. It's unfortunately not the medical establishment that is making a big deal about such issues.
There now exist a lot of evidence that suggests that about 90% of the health care expenditure in Western countries can be accounted for by lifestyle factors. If everyone consumed only whole foods, limited meat intake to small amounts and would do a lot of exercise, then the rates of heart disease, strokes, common cancers, type 2 diabetes etc. would be an order of magnitude lower. It's probably just a matter of time before governments will start to take measures to force people to stick to a healthy lifestyle. A possibility is that insurance companies will be allowed to offer lower premiums to people who agree to their health and lifestyle to be monitored. People like me who already stick to a healthy lifestyle will then switch to such insurance companies and pay a lot less, other people who are addicted to eating Big Macs will finally see the real price of their bad habits. Count Iblis (talk) 19:39, 25 March 2017 (UTC)
Near starvation diet does improve biological parameter: blood pressure, BMI, blood sugar, at least temporary, before the subject dies of course :-) however on a large scale the food really has nothing to do with obesity. If the reverse were true we would not see slim and even skinny people around, everyone would have been fat. Look at documentaries shot around 1900, almost everyone had been slim or at least of normal proportions and nobody, nobody suffered from the lack of food back then, nobody starved. So, why so many people are obese now. Obesity is a biological, evolutionary phenomenon and can be blamed on progress of medicine. Before modern era, until Pasteur demonstrated that some diseases are caused by bacteria, and in the era of epidemics, out of 10-12 children only 2 or 3 survived and those who died could have become overweight or obese had they grown to adulthood. Their immune system could not manage the challenge of measles, scarlet fever, mumps and other infections. Overweight and obese start with the skeleton which is typically wider. You can see it in their pelvis and shoulders. Overweight people need more food to maintain their fat mass which is much larger, otherwise they are hungry all the time. --AboutFace 22 (talk) 20:15, 25 March 2017 (UTC)
The obese people I have encountered don't eat a lot, way less than I do calorie-wise, but they eat a junk food diet and they don't exercise. While they eat more than what they would eat had they been slimmer, their higher energy needs for carrying their fat mass around doesn't compare to my energy needs due to heavy exercise every day. One hour of fast running will burn more than 1000 Kcal, the metabolic rate needed to sustain this on the long run needs to be a factor of 3 to 4 higher than this, which is why I eat 4000 Kcal a day and still have a low body weight of about 55 kg. The healthier you are, the more you'll look like Frank Medrano. Count Iblis (talk) 20:51, 25 March 2017 (UTC)
This Wikipedia article [21] states otherwise, refuting the Count Iblis's claim. I quote: "The view that obese people eat little yet gain weight due to a slow metabolism is not generally supported.[6] On average, obese people have a greater energy expenditure than their thin counterparts due to the energy required to maintain an increased body mass." The obese people may eat moderately in public but make up with additional food at home and they also eat more frequently. They really need more energy. --AboutFace 22 (talk) 21:00, 25 March 2017 (UTC)
Everyone up there says: You are obese because you don't exercise. This is ridiculous. Many slim people don't exercise at all or do it sporadically. On the other hand try to load yourself with 50 pounds of extra weight and go running. I want to see how far you will go. --AboutFace 22 (talk) 21:22, 25 March 2017 (UTC)
I do agree with these facts, they do eat more because they need to support their larger body mass. Now, given that if I were obese, my larger energy intake would be balanced by me having to carry more bodyweight around, I choose to burn that and a lot more energy by exercising hard. So, I can be at a low bodyweight despite eating 4000 kcal of healthy foods. Also, I have yet to see someone who is obese who doesn't have an obvious medical problem causing that (e.g. thyroid problems) and who only eats healthy foods like I do (at least 1 kg of fruits and vegetables a day, at least 70% of calories from whole grains etc.). Count Iblis (talk) 21:55, 25 March 2017 (UTC)
If you look at the paleo diet, there would have been a lot more gathering than hunting success, so more carbs than fat, especially if much of the fat burned off when cooking the meat over the fire on sticks. However, prior to the invention of milling, grains were not very edible, so those carbs would have largely been from root vegetables (starches) and fruit (sugars). Also, the animals that were killed and eaten would have been far leaner than modern, corn-fed cattle and hogs. StuRat (talk) 21:28, 25 March 2017 (UTC)
Count Iblis comments rings a bell ! Obese people appear to have trouble feeling long term satiety. Their body wants those things that are missing in their diet, so the individual feels very quickly hungry again but eats the same food that that causes the hunger in the first place, regardless of the calorific value. Thus, caught up in viscous circle. A ancient prophet once said you can not live on bread alone. Yet some modern humans are trying to go against this ancient wisdom. Leaves them with little 'motive' energy to run up the stairs (which is quicker) instead they wait for the elevator - which gives them the chance to pause, to think, about how hungry they feel... Eat a balanced diet.--Aspro (talk) 21:45, 25 March 2017 (UTC)
One reason the medical establishment originally "blamed fat" was a failure to distinguish between different types of fat, like unsaturated fat, saturated fat, and trans fats. Of course, at the time, food products, in the US at least, were only labelled with fat content, and did not break it down by type. So, if that was all the info you had, then avoiding all fat wasn't a terrible strategy, since there was so much trans fat and saturated fat you couldn't otherwise avoid. StuRat (talk) 22:37, 25 March 2017 (UTC)
AboutFace 22 said "Look at documentaries shot around 1900, almost everyone had been slim or at least of normal proportions and nobody, nobody suffered from the lack of food back then, nobody starved." However, List of famines would seem to disagree with around 45 famines listed from 1900 to present. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 00:28, 26 March 2017 (UTC)
Such as in concentration camps in the Boer war. StuRat (talk) 01:06, 26 March 2017 (UTC)
What do they have to do with the documentaries of the United States cities we see in the channels? Nobody kept the documentaries of famines of peoples in the Soviet States. Current obesity epidemic has nothing to do with abundance of food. --AboutFace 22 (talk) 01:22, 26 March 2017 (UTC)
Sure it does. Abundance of food = dirt cheap prices = overeating. And, in particular, unhealthy food is cheap in the US, because of government subsidies, aimed at things like meat, potatoes, and milk, rather then berries, nuts, and veggies. StuRat (talk) 01:50, 26 March 2017 (UTC)
AboutFace 22 you never said anything about it being confined to starvation in the US. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 02:37, 26 March 2017 (UTC)
See also here. Count Iblis (talk) 02:00, 26 March 2017 (UTC)

Also interesting:
"A high carbohydrate diet of rice, plantain, manioc and corn, with a small amount of wild game and fish – plus around six hours’ exercise every day – has given the Tsimané people of the Bolivian Amazon the healthiest hearts in the world."

"“This study suggests that coronary atherosclerosis [hardening of the arteries] could be avoided if people adopted some elements of the Tsimané lifestyle, such as keeping their LDL cholesterol, blood pressure and blood sugar very low, not smoking and being physically active,” said senior cardiology author Dr Gregory S Thomas from Long Beach Memorial Medical Centre in the US.

“Most of the Tsimané are able to live their entire life without developing any coronary atherosclerosis. This has never been seen in any prior research. While difficult to achieve in the industrialized world, we can adopt some aspects of their lifestyle to potentially forestall a condition we thought would eventually effect almost all of us.”"

Count Iblis (talk) 02:25, 26 March 2017 (UTC)

Carbohydrates are not essential for human nutrition [22][23] Despite this, the medical establishment supports the pseudoscientific theory of balanced diet that 50 to 60 percent of your total daily calories should come from carbohydrate. Is not this view similar to the view of the astronomy community 500 years back that the Sun revolves around the earth? --IEditEncyclopedia (talk) 09:20, 26 March 2017 (UTC)

[citation needed] for your claim it's pseudoscience. As others have said you can't rely on popscience books, flawed evolutionary explainations or simplistic 'well it's not essential' ones to make such bold claims, that's not how science works, nor is it logical BTW. This is the science reference desk, not the Daily Mail science pages. P.S. As for funding issues, if you think the various vegetable oil industries, the meat industry, the dairy industry etc aren't extensively involved in funding research, you need to do a lot more reading. Nil Einne (talk) 10:45, 26 March 2017 (UTC)
Your reasoning is full of fallacies. "Popscience" is a faulty generalization, you need to look at the contents, not on stamps. The Case Against Sugar is reviewed in leading mainstream newspapers like NYT, Guardian, FT etc. By your reasoning, Cosmos (book), The Naked Ape, A Brief History of Time are unreliable books. And don't make use of irrelevant comparisons like Daily Mail. No one is talking about Daily Mail here. And the "flawed evolutionary explanation" statement is an argument by assertion. --IEditEncyclopedia (talk) 10:56, 26 March 2017 (UTC)

Satiety - dietary fat or dietary fiber?

I've heard and read that dietary fiber regulates digestion and creates a sense of fullness. I've heard and read that dietary fat creates a sense of fullness, while sugar inhibits fullness. Okay, fine. How about eating something like an avocado, nuts, seeds, and mushrooms in a meal? Avocados, nuts, and seeds are relatively high in fat compared to carbohydrate and protein content, and mushrooms are relatively high in protein. Is satiety even measurable? Is it easier to reach satiety with a combination of both dietary fat and fiber, or is one better than the other? 50.4.236.254 (talk) 22:14, 25 March 2017 (UTC)

Well, you can measure satiety indirectly with surveys and by recording how much more of the same item people eat after a meal. And a combo is likely better than one or the other, although, if the goal is to lose weight, the dieter may want to emphasize dietary fiber over fat, since it had no calories. StuRat (talk) 22:30, 25 March 2017 (UTC)
I wonder how the researchers would deal with confounding variables. One participant may be given a high-fat food (almonds) or high-sugar food (cherry). The cherry is sweeter and may be more appetizing than the almonds that are just eaten raw and plain. Then, the researcher would probably conclude that high-fat is filling, even though it may be the taste or personal preference of the participant. The researcher could swap out the almonds for a piece of fatty bacon, but not everybody likes bacon because of the extreme saltiness. 50.4.236.254 (talk) 22:59, 25 March 2017 (UTC)
First give group A, X calories of high-fiber food, and measure how much of food Y they eat after. Then give group B, X calories of high-fat food, and measure how much of food Y they eat after. One week later, repeat the study, with the groups reversed. Not perfect, and the foods aren't going to be pure fiber and pure fat (and still be edible), but good enough to see the trend. A mixed fat and fiber group may also be added. StuRat (talk) 00:06, 26 March 2017 (UTC)
Its a bit more complicated yet simple. For instance, the Inuit (which I think is the pleural too) up in the far north, had a very high fat, low fiber diet, yet they had very low incidences of modern health problems until they adopted modern food stuffs. Dietary fiber does give the sensation of fullness but a high fat diet also provides satiety. Its satiety that you want to aim for. Start off with the paleo diet, then listen to your body telling you what it needs. Not what the food industry needs you to buy to incease their profits. Don't have to follow any fancy dietary régime – just listen to your body. This next bit is stupidly simple. After a meal – is your mind clear. After a meal – do you fit to take on the World. If yes to both questions, you are probably eating right.--Aspro (talk) 23:21, 25 March 2017 (UTC)
Pleural isn't plural, it's singular, even though there are two lungs. :-) StuRat (talk) 23:57, 25 March 2017 (UTC)
Inuit cuisine and Inuit is plural and Inuk singular. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 00:13, 26 March 2017 (UTC)
Interesting — I didn't know that about the singular. I did know about the mess about "Inuit" versus "Eskimo". Short version: In Canada "Inuit" is usually preferred and "Eskimo" is one of those slightly risky words, not exactly a slur but something people learn to avoid. But that's because anyone in Canada who would be described as "Eskimo" probably is Inuit. The use of "Inuit" doesn't translate well to Alaska, where it's just plain inaccurate, so "Eskimo" is probably going to stick around a while, refined sensibilities notwithstanding. --Trovatore (talk) 00:45, 26 March 2017 (UTC)
• Talk to a dietician and an endocrinologist if your general practitioner recommends it. Experiment on yourself, and keep a journal. I have lost 40lbs after bariatric surgery in January. But I have noticed my hunger pattern has changed, and have had a variety of discomforts.
I used to find food unappealing before the mid afternoon, a pattern for the last 30 years. I'd then have two normal meals, usually high in carbs (back when fat was evil) and then end up binging at bedtime. When I went off carbs after being diagnosed as diabetic, I still didn't eat in the morning, but then I had two all-I-could eat meat and salad meals. Then at bedtime, a tablespoon of peanut butter or 100g of black beans would quite satisfy me.
Since the surgery, I have been on a very high protein diet, with three small meals a day, and still low in carbs and fat. The surgery made me unable (and not wanting) to eat more than 100g, usually 2/3 meat, 1/6 veg, 1/6 starch at one sitting. But since the surgery I have been waking up starving, even if my blood sugar is 140. (I discontinued all diabetes meds with the approval of the doctor, as my blood sugar didn't warrant it.) Yet 30 minutes after a meal I would be hungry again to the point of distraction, even though I was eating the equivalent of a lb a day.
The nutritionist said that getting all my calories from protein was causing the hunger, and suggested two things: avoid any protein supplements except for whey; add ground flax seed (Metamucil until I go grocery shopping next) and eat banana, rice, applesauce and toast (see brat diet). Over the last week, the constant starving has gone away, my morning eating is normal, a tablespoon of peanut butter is my bedtime snack, and the other discomforts I had been suffering are greatly ameliorated.
But that's me. You can't expect to find a one-size fits all solution. μηδείς (talk) 03:07, 26 March 2017 (UTC)
An all bratwurst diet does sound good. :-) StuRat (talk) 03:57, 26 March 2017 (UTC)
I lost 20lbs one summer by eating only mozzarella sticks and froot loops. That may explain a lot. μηδείς (talk) 04:10, 26 March 2017 (UTC)+
Like why you are loopy ? StuRat (talk) 04:17, 26 March 2017 (UTC)

Wind direction, high and low

I've asked this before, but still don't get it.

This says the wind is going from east to west (an east wind). This (click play) says the wind is going from west to east (a west wind).

From what I remember being told, the first link reports ground level wind, and the second reports higher wind. Is this right?

If this is right, does that mean Haikou is now getting its weather from Vietnam rather than Hong Kong?

Many thanks, and sorry to bother you all again with this.

Anna Frodesiak (talk) 23:04, 25 March 2017 (UTC)

Sick and then not sick again for a long time

After you get a cold or flu, you don't get it again for a while. You never get another flu a week later. Why? Anna Frodesiak (talk) 23:04, 25 March 2017 (UTC)

See epidemiology. A pathogen spreads by any sort of contact. It may be macroscopic contact (you touching a doorknob) or microscopic contact (you breathing in water vapor from someone's sneeze). Your body attempts to fight these foreign invaders and builds immunity so that you don't get sick again. 50.4.236.254 (talk) 23:23, 25 March 2017 (UTC)
Immunity (medical)--Aspro (talk) 23:27, 25 March 2017 (UTC)
But you build an immunity to that exact bug, right? So how come you don't just get another bug. There are lots of them. Best, Anna Frodesiak (talk) 23:50, 25 March 2017 (UTC)
Common cold notes that there are over 200 viral strains. Your question is similar to what I've always understood. Although the article doesn't say it, the immunity you develop for a cold is supposedly to a specific virus. So if you get exposed to another cold virus sometime later, you could be vulnerable. People seem to get fewer colds as they get older, and one theory I've heard is that each time you get a cold, your immune system checks off another strain. However, as the article notes, colds are caused by exposure, and kids seem to get exposed a lot more often. ←Baseball Bugs What's up, Doc? carrots→ 23:55, 25 March 2017 (UTC)
You might, but there is usually only one flu bug and one cold bug in circulation at any one time. Abductive (reasoning) 23:58, 25 March 2017 (UTC)
Ahhh, I see. Okay, that explains it. Many thanks! :) Anna Frodesiak (talk) 00:05, 26 March 2017 (UTC)
I don't think that's correct. As noted in Influenza vaccine, multiple strains are included in the vaccine every year. ←Baseball Bugs What's up, Doc? carrots→ 00:06, 26 March 2017 (UTC)
No, silly rabbit, that is done in an attempt to predict which strain will win. Abductive (reasoning) 02:33, 26 March 2017 (UTC)
Anecdotally, when my mother worked in preschool, she would get at least 3-4 colds/other bugs every winter. Since she retired 5-6 years ago, I think she's been sick once. Kids are germ factories. --47.138.161.183 (talk) 00:01, 26 March 2017 (UTC)
Yes, they are total germ factories! They're all jammed (jambed?) together in schools and have a lot of physical contact. Speaking of jam, their hands are always sticky, and if you ever let them have a sip of your drink, hold it up to the light after. It will be filled with an enormous amount of backwash particles, even if they've had nothing to eat. Try it and see. Extraordinary! :) Anna Frodesiak (talk) 00:05, 26 March 2017 (UTC)
A good argument for teleteaching, especially if the anti-vaccination lobby gets more converts and the diseases become deadly.
On an episode of 3rd Rock from the Sun the (alien) family thought they were under biological attack: "They've sent in a human petri dish in a miniskirt to infect us !" StuRat (talk) 00:12, 26 March 2017 (UTC)
I've had back-to-back colds (a week apart, say) over the holidays, especially from my niblings visiting. It's actually become somewhat of a morbid family joke, asking what symptoms we should expect a few days after their arrival. But otherwise, I've certainly gotten sick far less often as I've aged, and the severity of the colds is much less. Can't remember the last flu I had, probably the late 80's, before I started getting the shot. Bronchitis is what I dread, but that's bacterial.μηδείς (talk) 02:40, 26 March 2017 (UTC)
If you were in your late 80's when you last had a flu, it's no wonder you can't remember. :-) StuRat (talk) 03:20, 26 March 2017 (UTC)

March 26

Can food be made to be suitable for both dogs and humans?

I was checking this ad about Rachael Ray's Nutrish Dog Food. It had chicken, rice, fruits and vegetables. This made me think what would happen if a human just prepares a meal with chicken, rice, fruits, and vegetables, cooks it, and then feeds the meal to the dog. Assuming that the dog is treated like a human family member with specific food needs (such as no garlic or salt or sugar), can food be prepared in a way that would be suitable for both human and dog? How much overlap is there between the nutritional requirements of human and dog? 50.4.236.254 (talk) 01:59, 26 March 2017 (UTC)

Quite a bit of overlap. But the question is if there is anything vital to one which is deadly to the other. Assuming not, there's still the issue that a dog diet is mostly meat, and that's not the best diet for people. If that's the only issue, you could have dog food plus something extra for the people (more fruits, veggies, onions, beans, nuts, mushrooms, etc). Also note that some foods that might not harm your dog might cause undesirable effects, like beans and onions. StuRat (talk) 02:03, 26 March 2017 (UTC)
The Nivkh people, of Northern Sakhalin and the Amur river traditionally hunted fish which they buried in pits and pickled. They then fed the season's batch to dogs, which canines they then ate. on eating dog. μηδείς (talk) 02:33, 26 March 2017 (UTC)
I am old enough to remember when it was quite common to feed one's pet dog with leftovers from meals. The concept of packaged pet food in its infinite varieties is relatively new. One didn't see too many obese dogs then. Richard Avery (talk) 07:26, 26 March 2017 (UTC)

Why don't they make non-hybrids with 2 or 4 internal combustion engines?

Each driving half or 25% of the wheels and a computer doing everything the mechanical linkages like differentials used to do. Smaller engines have higher power to weight ratios. Sagittarian Milky Way (talk) 02:56, 26 March 2017 (UTC)

Are you sure that smaller internal combustion engines are more efficient, including all the connection lines and hoses for spark plugs, fuel lines, air supply, cooling, controls, etc ? I don't think of small gasoline engines, like lawn mower engines, as being very efficient. Small electrical engines, on the other hand, do seem efficient, so having one drive each wheel does seem like a viable option. StuRat (talk) 03:03, 26 March 2017 (UTC)
I speculate that IC engines are not responsive enough to support sufficiently precise control of torque and RPM to eliminate the differential. In addition, an IC engine is efficient over only a small range of RPM, so the engines will all require gearboxes, and this negates most of the potential gains. By contrast, electric motors are quite responsive and do not need to shift gears to maintain efficiency. -Arch dude (talk) 03:33, 26 March 2017 (UTC)
The "Sahara" model of the Citroën 2CV had two engines to create a 4-wheel-drive system for desert travel. -Arch dude (talk) 03:33, 26 March 2017 (UTC)
It would waste energy. Only a fraction of the energy consumed by an automobile's internal combustion engine actually goes to the wheels. See: File:Energy flows in car.svg, [24], [25]. If you have two engines, now you're wasting twice the energy. Actually it's even worse than that, because you have the added weight of the extra engines, plus you would need to design the cooling systems, drivetrain, etc. to accommodate the multiple engines, which adds even more weight (not to mention more stuff that can break). Electric motors are a lot lighter, more efficient, and generally provide much better torque than an ICE; that's why multiple electric motors can make sense. Compare this breakdown of electric vehicle losses to what I linked before. --47.138.161.183 (talk) 03:49, 26 March 2017 (UTC)
It's not quite that bad, because each engine is smaller and/or run slower. StuRat (talk) 03:51, 26 March 2017 (UTC)
If they do this anywhere, certainly it will be with those mining trucks that have tires the size of houses. I'm no expert, but I'd look there, for the same reason that large dinosaurs often had secondary ganglia to handle impulses to far from the brain. μηδείς (talk) 04:06, 26 March 2017 (UTC)
Such large vehicles usually use diesel-electric transmission. Yes, it actually saves energy to have an ICE turn an electric generator and then use electric motors to turn the wheels, because you can dispense with the extremely large and heavy transmission that would otherwise be required, and the ICE can then always turn at its most efficient RPM range. --47.138.161.183 (talk) 04:16, 26 March 2017 (UTC)
This reminds me of Diesel-electric locomotive and variants. PaleoNeonate (talk) 05:16, 26 March 2017 (UTC)
Yes, diesel-electric locomotives use a diesel-electric transmission as well (the lead image on the latter article is a locomotive). Some large ships also use it: integrated electric propulsion. (On a side note I think the big batch of marine propulsion articles could use some cleanup and merging.) --47.138.161.183 (talk) 09:26, 26 March 2017 (UTC)
As OP didn't say this is about road vehicles, what about diesel-hydraulic multiple units? Every car (or maybe 2 out of 4 cars) has its own diesel engine to power the axles of that car, as it's not feasible to have mechanical power transmission from one car to another. Diesel-electric multiple units may use a single engine with electrical transmission to other cars, or multiple engines for reliability or space considerations: multiple small engines can be put under the floor, a single big one needs an engine compartment. Although a single big engine is somewhat more efficient. PiusImpavidus (talk) 09:57, 26 March 2017 (UTC)
• This is difficult to arrange, but has been done. Mostly it's an issue for petrol engines. Petrol engines are throttled to control their power, so they are inefficient at part-throttle. The situation is much better for diesel engines, which are controlled by their fuel supply.
A few vehicles, mostly larger ones, have used multiple prime movers, switchable individually. Larger ones have more fuel to save, more scope for the "overhead" of the switching and may need multiple power units anyway, just on the size basis. On railways the British Rail Class 55 Deltic (diesel-electric) could do this, as could the diesel-hydraulic Class 52 Westerns, both with two engines. The Deltic could drive all of its traction motors in such a case, the Western only drove a single bogie. On ships, an electric transmission is often used to arrange this control from multiple engine-generator units.
For cars, the Cadillac L62 engine first used a system of switching pairs of cylinders for its V8 engine in and out of use. Andy Dingley (talk) 10:36, 26 March 2017 (UTC)
• The claim that "petrol engines... are inefficient at part-throttle" seems very odd in view of the standard advice that using the highest possible gear for the circumstances—thus, throttling the engine down as much as possible—produces the greatest fuel economy when driving a car. --76.71.6.254 (talk) 11:53, 26 March 2017 (UTC)
The advice applies to cruising at constant speed where less than maximum engine power is required. "The engine in a car cruising on a highway is usually operating significantly below its ideal load, because it is designed for the higher loads required for rapid acceleration." Using highest possible gear implies the engine delivering near its maximum power at a low r.p.m. i.e. near full throttle.[26]. Blooteuth (talk) 14:47, 26 March 2017 (UTC)