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"A calorie is a calorie" violates the second law of thermodynamics

ncbi.nlm.nih.gov

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Re: "A calorie is a calorie" violates the second law of thermodynamics

#61

Post by eru »

janjan wrote: post #36
jvdongen wrote: post #25

The car/fuel analogy is a bad one. High-test fuel only makes sense if the engine in which you intend to burn it is designed to actually make use of its qualities to reach higher efficiencies (e.g. a higher compression ratio). If not, you're just burning more expensive fuel at the same efficiency. That said, what really interests me is the mechanisms behind addictions. Why do smokers smoke, knowing full well by now th…

> That said, what really interests me is the mechanisms behind addictions. Why do smokers smoke, knowing full well by now that it will kill them earlier than non-smokers? Why stuff obese people themselves, knowing full well that it will cause serious health issues down the line. Let's take this one step further: Is the reason/mechanism a smoker smokes the same why I browse reddit and HN all day instead of working on…

Probably not completely the same. There's a variable reward schedule behind browsing HN (and that can be addictive). Smoking seems to give a different `reward'.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#62

Post by haploid »

zecg wrote: post #56

I have found the perfect diet (or, rather "weight control algorithm"), have lost about 60 pounds and haven't gained them back for a couple of years now. The algorithm is extremely simple: "If you ate yesterday, don't eat today." It means I fast AT LEAST half days in a year (see: alternate day fasting). On fasting days, I drink water and green tea (with no sugar, of course). It has numerous purported health benefits.…

This sounds like an excellent way to live with chronically high cortisol levels and ensure that you never retain significant muscle mass.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#63

Post by woobar »

hackermom wrote: post #47

This is entirely besides the point of the study and the article, but why are the Americans the only ones who, in terms of human energy intake/consumption, say calorie when it should be kilocalorie? Why do they insist on being one thousand times off? "It's easier"? From where does this come from, and why does the rest of the world insist on being accurate?

Americans use term 'Calorie', not 'calorie'. 1 Cal = 1000 cal

http://en.wikipedia.org/wiki/Calorie

Re: "A calorie is a calorie" violates the second law of thermodynamics

#64

Post by hackermom »

woobar wrote: post #63
hackermom wrote: post #47

This is entirely besides the point of the study and the article, but why are the Americans the only ones who, in terms of human energy intake/consumption, say calorie when it should be kilocalorie? Why do they insist on being one thousand times off? "It's easier"? From where does this come from, and why does the rest of the world insist on being accurate?

Americans use term 'Calorie', not 'calorie'. 1 Cal = 1000 cal http://en.wikipedia.org/wiki/Calorie

...and the case-sensitive nature of this confusion is exactly the point I'm trying to get across - people just don't know the difference. A Calorie is a calorie! Just read the nutritional declaration on a few American food products and you'll find an equal amount of both. MB, Mb or mb, anyone?

Re: "A calorie is a calorie" violates the second law of thermodynamics

#65

Post by run4yourlives »

colomon wrote: post #42
run4yourlives wrote: post #12

"A calorie is a calorie" is good enough, however. People aren't fat because they are consuming 2500 calories from a Big Mac and Fries rather than 2500 calories from carrots. People are fat because they are consuming 6000 calories and burning off 1300. The message is simplistic, sure. For a large majority of overweight people though that's all that is required. Somewhere between reducing caloric intake and becoming fi…

Errr.... consuming 6000 calories and burning off only 1300 would cause you to gain more than a pound. That might be a daily intake for someone weighing 600 pounds, but it's hardly the situation for your run-of-the-mill fat person. Putting it in practical, personal terms -- I was laid up for six weeks for medical reasons this winter, and my bad habits continued for the next six weeks as well. Over that period I gained…

It was an exaggeration to make the point. Sorry, thought that was obvious.

For your example: If you had eaten a low-carb diet, you'd probably need to have eaten 50% more food in terms of quantity in order to meet the caloric intake you were getting on the "whatever" diet.

That's my point. If you simply focused on the caloric intake and kept it at 18,000 a week (which seems high for someone lying in bed, to be honest) and still ate whatever you wanted, you would't have put on 18 pounds.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#66

Post by woobar »

hackermom wrote: post #64
woobar wrote: post #63

Earlier quoted context omitted.

Americans use term 'Calorie', not 'calorie'. 1 Cal = 1000 cal http://en.wikipedia.org/wiki/Calorie

...and the case-sensitive nature of this confusion is exactly the point I'm trying to get across - people just don't know the difference. A Calorie is a calorie! Just read the nutritional declaration on a few American food products and you'll find an equal amount of both. MB, Mb or mb, anyone?

I've reread you original post and don't see any mention of case sensitivity. In fact you insisted that americans use inproper unit (1000 times off), which is not true at all.

Also, I always pay attention to food labels and never noticed any confusion. As far as I can tell the units on Nutrition Facts label are always correct.[1]

[1] http://www.google.com/search?q=nutrition+label&tbm=isch

Re: "A calorie is a calorie" violates the second law of thermodynamics

#67

Post by Geee »

saalweachter wrote: post #58
Geee wrote: post #39

Earlier quoted context omitted.

This is actually pretty interesting point of view. In essence, you should try to breath out all the carbon you ingest. Measuring the carbon dioxide output would be a pretty accurate measure of the actual energy consumption in the body.

I wonder if you could proxy your carbon dioxide output off of your breathing, with some calibration? When I run, I breathe harder; am I expelling more or less carbon dioxide per breath than when I am sitting in a chair? Counting breaths seems pretty technically feasible. Maybe your heartbeat could also work; that's also pretty easy to collect. It'd be awesome to have a running total of how many calories I'm burning a…

Polar heart rate monitors give you an estimate of the burned calories based on your pulse. That can't be too accurate though, because some people have bigger hearts which pump more blood per beat.
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