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0 pointsajslater15y ago0 comments

I'd bet a fair amount that your Mass General study used self reported calorie intake.

800kcals a day is typically enough for a 100 lb person to lose nearly a half a pound of fat a week. That's low calorie by most people's measure. Certainly mine at 200lbs

When most people are talking about 'losing weight' they mean losing fat. At least losing actual body tissue. Anyone can gain or lose 10% of their body weight in a few days by controlling for carbs. But its just water.

Try to ignore rat studies if you possibly can. Their metabolism, particularly their capacity for denovo lipogenisis is very very different than that of human beings.

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beagle315y ago· 1 in thread

> I'd bet a fair amount that your Mass General study used self reported calorie intake.

99% of nutrition studies are, but this one wasn't. I can't find the reference now, though.

Personally, I've been on a ~1200kcal/day diet for years (for some of that time, I did very detailed tracking), and stayed at my 220lbs. Which, of course, makes no sense, and it didn't to my girlfriend at the time who was an MD - so she decided she'd show me how wrong I am by eating the same as me. She lost weight quickly and started blacking out (apparently some form of malnutrition) within a few days, and stopped after a week with a SEP field resolution ("Contradicts everything I know, so I'm just going to ignore it").

Then, 12 month ago, on essentially the same diet, I started gaining weight - slowly but surely. And then I decided to cut away wheat, and lost 30 pounds within a month. (In retrospect, I also noticed that my gain weight coincided with going from pure-egg protein powder to egg-and-wheat protein powder).

There are about a thousand more variables than calories, and the body can change its efficiency.

Ignore the rat studies if you like, but cabanac has similar experiments with humans -- basically, people fed through a nose tube lose weight almost independently of the amount of calories you put in their stomach. Body just doesn't use the food unless proper signaling (apparently, scent related) happens.

ajslaterOP15y ago

So, for the uninformed peanut gallery, beagle3 is just plain wrong. Probably not intentionally, he's likely also fooling himself. But you locked him in a room and measured his food for him and really only fed him 1200kcals per day, even at a fairly sedentary level of exercise, a 220lb man would lose a lot of fat mass over several weeks. And no beagle3, human bodies tend to be very greedy with calories and do a good job absorbing them regardless of what you smell.

What likely happened is that reducing carbs reduced beagle3's appetite and he ate less. Unless...

...unless beagle3 has a magic body that has never once been seen in any controlled experiment. But he probably does, since every dieter who has problems believes they have a special body that science can't explain. So they buy a book and a program from someone who tells them what they want to hear. And if their guru is on their game they sell very very expensive supplements.

Because its a well known scientific fact that the first law of thermodynamics applies to everything in the universe except a disgruntled dieter.

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