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Two mind-blowing revelations for the price of one!
December 8, 2011 2:46 PM   Subscribe

Energetic consequences of thermal and nonthermal food processing. Or, as discussed by Discover Magazine, Why Calorie Counts Are Wrong: Cooked Food Provides a Lot More Energy. (N.B. second link references a video of house mice eating a baby albatross alive.)
posted by d. z. wang (36 comments total) 22 users marked this as a favorite

 
Dude, your warning needs a warning. :)
posted by jwhite1979 at 3:00 PM on December 8, 2011 [8 favorites]


Coming soon: Raw steak diet. Eat all the steak you want, without getting fat. All you have to is not cook it.
posted by delmoi at 3:01 PM on December 8, 2011 [2 favorites]


Metafilter: I had even myself tried chewing monkeys killed and discarded by chimpanzees
posted by qxntpqbbbqxl at 3:02 PM on December 8, 2011 [4 favorites]


This is pretty fascinating. I was particularly struck by this comment in the second link:
"...the average woman on a 100% raw diet did not have a functioning menstrual cycle. About 50% of women entirely stopped menstruating!"
I wish I could read the whole paper it references. That's a crazy percentage and it's really not clear what exactly "100% raw diet" means in this case.
posted by restless_nomad at 3:05 PM on December 8, 2011 [1 favorite]


I knew this from Minecraft.

I can also offer revelations re: raw meat and food poisoning.
posted by six-or-six-thirty at 3:09 PM on December 8, 2011 [2 favorites]


The 50% menstruating figure is from the book 'Chasing Fire', which also discusses the cooked/uncooked stuff…when I read it I thought it was a very important point that wasn't given due significance.

When it comes to things like calories, it doesn't really matter how accurate the measurements are, just that a form of measurement exists. It's a bureaucratic thing rather than a scientific thing. Look around for an article called 'The Imperialism of the Calorie' which discusses the rise of the calorie as a political tool.

I've actually found myself doing a nutritional science degree in which we're expected to formulate largely bogus nutritional histories for people. It's a little like making up an astrological chart, and pretty much just as scientific.
posted by chrisgregory at 3:12 PM on December 8, 2011 [6 favorites]


Coming soon: Raw steak diet. Eat all the steak you want, without getting fat. All you have to is not cook it.

If it weren't for the food poisoning implications, I would be all over that.

I think I might have issues.
posted by Mister Fabulous at 3:21 PM on December 8, 2011 [1 favorite]


This is why my calorie counting subsists of this: Am I gaining weight? I am probably getting too many calories. Am I losing weight? I am probably not getting enough calories.
posted by midmarch snowman at 3:27 PM on December 8, 2011 [5 favorites]


The whole raw food thing drives some anthropologists up the freaking wall. Like the dude referenced in this article suggests, cooking makes us human. Our guts are exquisitely evolved to eat a large variety of foods, and cooking has facilitated this.
posted by clvrmnky at 3:27 PM on December 8, 2011


Actually it's a lot more complicated than how accessible the calories are in cooked vs uncooked. There is something else that's not mentioned here, and that's the physiological cost of eating cooked vs uncooked. In other words, it's not just that some calories are not accessible in raw form, but that your body expends energy to obtain the calories that it does manage to pry out of the raw food through more lengthy and complex digestive processes enzyme releases etc. Basically, 100 calories that your body gets out of raw food costs it f.ex. 20 calories to get, whereas the same 100 calories it obtained from cooked food, only cost it 5 calories to extract, leaving more net. This by the way, is not simply true of the "raw" aspect. It's true also in situations like 100 calories gotten from eating whole fruit vs drinking 100 calories in fruit juice - it takes energy to extract the calories from whole fruit and liberate the nutrients from the cellular matrix and fiber, whereas you don't expend the same level of energy with a fruit juice. Yet both are raw.

Another fun way to play with this that has nothing to do with "raw". Take the same amount of a given fruit juice, but in one case chill it to almost freezing. You'll get net less energy from the chilled juice, because your body had to expend energy to warm it up! Again - nothing to do with "raw". So, if you really want to cut down on your caloric intake, eat raw, fibrous, and cold food... yum!

Bottom line - this article merely scratches the surface of the issue of calories and diet. The reality is far more complex and interesting.
posted by VikingSword at 3:35 PM on December 8, 2011 [10 favorites]


viking, I find the conversation about how sugar molecules entwine around each other to prevent digestion to be a bit more interesting than the old "But you need to SPEND ENERGY to WARM COLD FOOD!!" idea
posted by rebent at 3:51 PM on December 8, 2011


You'll spend even more calories and lose even more weight if you eat raw LIVE animals.
posted by TheRedArmy at 3:55 PM on December 8, 2011 [5 favorites]


rebent, any conversation will be dull if you only absorb one sentence out of a statement.
posted by VikingSword at 3:56 PM on December 8, 2011 [1 favorite]


Wait... So this means if I'm trying to gain muscle mass, I need to eat my steaks well-done??? GODDAMMITALL!!!
posted by LordSludge at 4:03 PM on December 8, 2011


I can't wait to try Raw Twinkies.
posted by symbioid at 4:22 PM on December 8, 2011 [2 favorites]


EROEI
posted by ninjew at 4:42 PM on December 8, 2011


Wait... So this means if I'm trying to gain muscle mass, I need to eat my steaks well-done??? GODDAMMITALL!!!

Order the hamburger. Same experience, cheaper meal.
posted by Dark Messiah at 4:43 PM on December 8, 2011


Seems to provide an interpretation for some of this study's findings (previously).
posted by dsword at 5:48 PM on December 8, 2011


Like the dude referenced in this article suggests, cooking makes us human. Our guts are exquisitely evolved to eat a large variety of foods, and cooking has facilitated this.

I love fresh fruits and vegetables but I get sick as a dog if I eat a raw apple on an empty stomach.

As far as dieting goes, I've been drinking ice cold water for years. I don't have any evidence that it works as a dieting tool, but I figure it can't hurt and I prefer it that way.
posted by Secret Life of Gravy at 6:24 PM on December 8, 2011



Coming soon: Raw steak diet. Eat all the steak you want, without getting fat. All you have to is not cook it.


As long as I can have it ground up with a raw egg on top, I'm ok with this.
posted by Forktine at 6:27 PM on December 8, 2011


Seems to provide an interpretation for some of this study's findings (previously).

As the study so graphically shows, potatoes in all their forms can be very unhealthy in some ways. I always like to drag out this study when potatoes are discussed, to justify my anti-potato stance (and prejudice):

"González S, Huerta JM, Fernández S, Patterson AM, Lasheras C.
Differences in Overall Mortality in the Elderly May Be Explained by Diet.
Gerontology. 2008 May 26.
PMID: 18503250

RESULTS: Fruit intake was found to be inversely associated with overall mortality. Multivariate adjusted mortality rate ratio (95% CI) per 1 SD increase in fruit intake was 0.714 (0.519-0.981). On the contrary, each 1 SD of potato intake led to a 32% higher risk of death (RR (95% CI) = 1.319 (1.033-1.685))."[emph. mine VS]

So yeah, potatoes are poison /jk/!
posted by VikingSword at 6:43 PM on December 8, 2011


Food calories are actually kilocalories. 1 kcal is the amount of heat it takes to raise a kilogram of water 1 degree c. So unless you are eating ice, the most you could possibly get out of a 1L beverage is a 37 Calorie boost (or loss, depending on perspective.)
This is why my calorie counting subsists of this: Am I gaining weight? I am probably getting too many calories. Am I losing weight? I am probably not getting enough calories.
That's the trouble. The calories listed on the package are the chemical calories- literally burning the food in a laboratory and seeing how much heat is released- and not the amount of calories your body will extract from it. So the metric isn't just calories in = calories burnt + fat. If you are eating hard to digest (uncooked) foods, your body will extract less energy from it, even though its the same food. You can't substitute 100 calories of broccoli for 100 calories of mini-cupcakes and get the same results, even though common sense says you should.

This is why (among other reasons) why Atkins works. Meat has fewer calories per unit, and those calories are harder for the body to digest. Which is why rare steak will go right through you.

Not to mention, fruit and vegetable farts.
posted by gjc at 7:03 PM on December 8, 2011


As the child of a mother who did a lot of yoyo dieting when I was young, I've always assumed a lot of diet science was pseudoscience. Little did I know that the calorie counts in the food we were eating were equally pseudoscientific.
posted by immlass at 7:17 PM on December 8, 2011


This is just part of why "calories in/calories out" is wayyyy to simplistic for such a complex system as the human body.
posted by lubujackson at 7:41 PM on December 8, 2011


I read a fair number of Mefi threads relating to weight issues and dieting. They usually devolve into a bunch of people saying, "It's SIMPLE, folks: fewer calories, less weight!"

The conversation in this thread, on the other hand, is fascinating, nuanced, and complicated.
posted by meese at 9:09 PM on December 8, 2011


But seriously, I've long heard among body-builders (I'm not one, but I learn what I can from them) that protein in cooked eggs is more digestible than raw eggs. Looks to me that this may be true for meat as well.
posted by LordSludge at 9:13 PM on December 8, 2011


I'm confused about the experiment. I even read the paper in detail, looking for this point, but they said nothing.

It seems to me that it's obvious that cooked food has more energy. The cooked food is at a higher temperature than when it was raw, so it has more energy. Even a cup of hot water with no food value will give the body more energy than cold water. Even leaving aside the issue of calories the food itself, the raised temperature of the food brings some minor energy into the system. I want to know if the raw and cooked foods were at the same temp when the rats ate them.

Anyway, I thought that was the whole point of cooking, making it easier to digest and get more calories out of the food material.
posted by charlie don't surf at 9:34 PM on December 8, 2011 [1 favorite]


Food calories are actually kilocalories. 1 kcal is the amount of heat it takes to raise a kilogram of water 1 degree c. So unless you are eating ice, the most you could possibly get out of a 1L beverage is a 37 Calorie boost (or loss, depending on perspective.)

I may be wrong, but I think you're assuming that the body is a perfectly efficient heat source. While wikipedia may not mention the efficiency of converting calories to brown fat and then from brown fat to actual heat, but I can't imagine that it's that great.
posted by YAMWAK at 11:31 PM on December 8, 2011


I dont' understand your point gjc

If you drink 1L of cold water (almost frozen say 1C), then your body will need to raise the temperature of the water to 37C which will cost 36 kcal?
posted by mary8nne at 1:13 AM on December 9, 2011


As someone who is studying to be a registered dietitian, I can tell you that yes, kcal counts are ridiculously inaccurate. Activity levels vary and are difficult to quantify. The activity you do without noticing like fidgeting and tidying up, etc., varies significantly from person to person and is essentially unquantifiable. And yes, our software does not at all take into account the available kcal differences in raw vs. cooked food (the USDA database on which they are based claims 100 g of raw carrots have more kcal that 100 g of cook carrots, for instance). Your relative muscle mass controls the rate at which your burn calories when at rest, but lean body mass is impossible to measure accurately without expensive equipment -- so it's simply not done.

chrisgregory - It's "Catching Fire" by Richard Wrangham, the same author as the article, and yes, it's a brilliant book and I highly recommend it to anyone interested in this sort of topic, or the evolution of the human diet in general.

Forktine - I'd stay away from the raw eggs, not just because you only get half the protein from uncooked egg as previously mentioned, but also because the white contains avidin, which binds choline, making it unabsorbable. Choline is a very important vitamin for memory and deficiencies can lead to permanent changes in brain organization and function. The problem is that it is only found in decent amounts in organ meats and egg yolks. So if you don't cook your eggs, you're eliminating probably your most valuable source of the vitamin.

immlass - I'd stay away from anything combining "diet" and "science". The evidence from science shows that weight can only be lost long-term with permanent changes leading to slow loss (1-2 pounds per week depending on your starting BMI). If you go faster than this (by dieting) you lose muscle, which is the main thing dictating your metabolic rate. Permanent changes are also necessary because as you lose your kcal needs decrease, so you must consume less from then on. Exercising (60-90 min/day, most days of the week) to maintain lean body mass is also necessary to maintain muscle and prevent the plateau that inevitably happens.

YAMWAK - adult humans have barely any brown fat, so it's not really metabolically relevant. It basically wastes energy to produce heat for warming the body. Infants have a decent amount, and other animals do as well -- but not adult humans.
posted by antinomia at 5:31 AM on December 9, 2011


Forktine - I'd stay away from the raw eggs, not just because you only get half the protein from uncooked egg as previously mentioned, but also because the white contains avidin, which binds choline, making it unabsorbable. Choline is a very important vitamin for memory and deficiencies can lead to permanent changes in brain organization and function. The problem is that it is only found in decent amounts in organ meats and egg yolks. So if you don't cook your eggs, you're eliminating probably your most valuable source of the vitamin.

Steak tartar with no raw egg? Them's fighting words!
posted by Forktine at 6:10 AM on December 9, 2011


Or steak tartare, even.
posted by Forktine at 6:31 AM on December 9, 2011


If you go faster than this (by dieting) you lose muscle, which is the main thing dictating your metabolic rate.

I don't have any proof, except my own experience, but I believe having a higher muscle/fat ratio makes you burn more calories All The Time. Whether you're jogging, cycling, even watching tv or sleeping, a pound of muscle takes more energy to operate than a pound of fat. Maybe that's obvious, but it does imply that increasing one's muscle mass is important when trying to lose weight. Think of food as the energy intake and muscle/fat ratio as the burn rate. My guess is that this lean muscle burn rate is more significant, over the long haul, than the calories burned during actual exercise, but I'd love to see a study.

Exercising (60-90 min/day, most days of the week) to maintain lean body mass is also necessary to maintain muscle and prevent the plateau that inevitably happens.

Unless I'm just some sort of genetic freak, I'd say way less exercise time is required to build/maintain lean muscle mass. Years ago, I learned about the importance of eating enough protein when weight-lifting, and I packed on about 30 lbs of muscle in a year, lifting very heavy weights for about an hour once a week, but eating all the protein (eggs, meat, nuts, shakes, etc) I could stomach. Lifting more wasn't the key (I used to lift 3 hrs/day, but ate pretty light, and plateaued pretty quickly); proper diet for the goal was critical.

More recently, coming back off a neck injury which lead to me getting fairly out of shape, I started training Crossfit for 2-3 months, no more than once a week, and I've noticed some pretty significant muscle development. Granted, Crossfit is very intense (like make-you-wanna-puke intense) -- get your doctor's okay, YMMV, etc. -- but it's incredible what just 20-30 min a week plus proper diet will do. Gonna bump it up to twice a week when my body can handle it -- but gah so sore...
posted by LordSludge at 12:25 PM on December 9, 2011


Exercising (60-90 min/day, most days of the week) to maintain lean body mass is also necessary to maintain muscle and prevent the plateau that inevitably happens.

Yeah, that's a seriously high estimate. I've put on a substantial amount of muscle this year by lifting for 30 minutes three days a week, following a plan written for professional powerlifters. More time than that would actually be counterproductive. (It has way more to do with what you do than how long it takes you, and recovery is at least as important in maintaining or building muscle as the actual stimulus.)
posted by restless_nomad at 12:38 PM on December 9, 2011


If you drink 1L of cold water (almost frozen say 1C), then your body will need to raise the temperature of the water to 37C which will cost 36 kcal?

Yes. You'll burn 36 extra calories as your body warms up the liquid to body temperature. Which is like 2 Doritos worth.
posted by gjc at 4:33 PM on December 9, 2011


The reason I mentioned ice was because of the extra energy required to change the phase. Even though it only takes 37 Calories to warm that water from just above 0 to body temperature, it would take almost 80 Calories to melt 1L of ice from just under freezing to just over freezing.
posted by gjc at 4:38 PM on December 9, 2011


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