I think your explanations are both plausible, though I also think that it’s possible that the registrants were never meant to be that thin so they have to eat a very small amount to stay there; or that they screwed up their metabolisms dieting (anecdotally, some folks I have observed on Weight Watchers seem to lose quickly at first by being super-strict about points, eating under their points, or not eating activity points or whatever, then they plateau and the only way to continue losing is to restrict even further until they’re eating a ridiculously tiny amount. In a general sense I feel like it’s better to eat as much as you possibly can and still lose (even if it’s a very slow loss) so you have somewhere reasonable to go if you hit a plateau. Then again this doesn’t happen to everyone and it’s just anecdotal anyway, so I am not sure if the idea is worth anything).

The possibilities involved with increasing your muscle mass through strength training and possibly improving your metabolism that way are interesting. I definitely agree with you there.

But 1380 calories a day!?!?! Minus all that exercise!?!? That’s starvation level. I think the most likely explanations are (a) these people are grossly underestimating their food intake or (b) (more likely) they are cardio bunnies and their bodies have adapted to excessive amounts of cardio.

I’m telling ya – strength training is the answer (along with *moderate* cardio.

An abstract of a research paper at the NWCR site says “Mean (+/-SD) current consumption reported by registry members was 5778 +/- 2200 kJ/d, with 24 +/- 9% of energy from fat, Members also appear to be highly active: they reported expending approximately 11830 kJ/wk through physical activity.”

That sounds a lot more realistic.

I once worked out that to maintain my weight on my current calorie intake and exercise schedule I’d need to be 28. I’m 51 – but muscular. ;-)

Lucy, that is really interesting stuff about BMR and that kind of thing makes it clear that calories in=calories out is a gross oversimplification of the issue. I agree 100% with your comments too.

K, your attitude toward this whole thing makes me really happy. Maybe many of us could be a whole lot saner and healthier if we took your approach.

Btw, to figure BMR (basal metabolic rate):
655 + (4.3 * weight in lbs.) + (4.7 * height in inches) – (4.7 * age) = BMR

BMR is the calories it takes just to keep one’s body functioning if one were to stay in bed 24 hours a day.

Sorry, but you’re missing my point again. Over-exercising has two components: the physical exertion and the motivation to do so. I was speaking more to the latter. Also, I’m curious as to whether you have never heard of ED’ed pro gymnasts, pro figure skaters, runners, and exercise instructors? Heck, I looked into becoming an aerobics instructor so I could exercise several hours a day without raising suspicions.

“In fact, people in the NWCR reported eating an average of 1382 calories per day, while burning about 400 calories through exercise each day.”

That is not normal! The BMR of a 150-lb. woman needs about 1450 calories. That doesn’t take into account any type of physical activity. That’s how many calories it takes for her body to function if she stayed in bed 24 hours a day. What weight is maintained on 1000 calories a day?!? I shudder to think. It’s probably around 100 lbs. A thousand calories a day is about half what is recommended for adults. That’s downright scary.

“And I think, when you refer to overweight not being associated with health risks that you’re maybe referring to the 2005 study which associated overweight with a lower overall mortality? That study has been widely disputed, though, and is at odds with literally hundreds of others studies showing that overweight and obesity, in and of themselves, increase your risk of developing type 2 diabetes, heart disease, gallbladder disease, sleep apnea, osteoartritis, certain types of cancers and several other serious health problems.”

Nah, she’s probably referring to something more like http://www.bigfatfacts.com. You know, how overweight people actually have the same mortality rate as thin people. And that fat active people actually have a lower mortality rate than inactive thin people. Health isn’t determined by weighr, but rather whether one is sedentary or not.

There’s no proof, last I heard, that fat leads to diabetes and the other ailments you list. In fact, those diseases may cause people to be fat. They just don’t know. Those diseases and being fat are correlated, but there have been no causal relationships proven at this time. Read The Obesity Myth by Paul Campos (The Diet Myth in paperback). My gallbladder disease was caused by dieting, as a matter of fact.

To spacedcowgirl: Once again, an excellent comment I couldn’t agree more with. I think I’ll take a page from your book, though, and stop trying to beat my dead horse as well. If I haven’t made my points by now, I’m inclined to give it a rest because I don’t find arguing back and forth very therapeutic.

I mean, if I make myself miserable by keeping myself to a really rigid routine and beating myself up if I ever slip from it, I have a problem, even if I’m a “healthy weight”.

On the other hand, if my routines make my life less stressful and I don’t freak out if I have to deviate from them, then they are probably beneficial routines.

On the personal level, when I’m exercising and eating healthily I feel good about myself because I’m doing that, not because of the number on the scales. They make me feel good about the way I am now, not the way I might be if I keep doing this for X amount of time. That’s how I know it’s the right thing for me. I’m not saying it’s the right thing for everyone, or that anyone manages to do it all the time, because they don’t.

I think the OCD suggestion might have quite a bit of value – and I live in a house which is tidy because of my OCD husband! He gets anxious about his weight, right enough, even though he’s normal-to-thin (and always has been). He isn’t endangering his health either way, but he doesn’t forgive himself for eating an extra piece of cake.

If I was like that, would I be thinner? Probably. But I’d rather be me and not as thin.

The idea that yo-yo dieting damages one’s metabolism has not been validated by science but remains a popular misconception. However, it is established that once you have been obese, your body wants to stay that way. This is because obesity causes people to become resistant to the hormone leptin, and if they lose weight, their levels of leptin go down causing further leptin deficiency. Leptin’s function is to promote leanness through curbing appetite and increasing energy expenditure, so reduced leptin function means you’re going to have a slow metabolism and a big appetite. Hence the trouble with losing weight and keeping it off.

And I think, when you refer to overweight not being associated with health risks that you’re maybe referring to the 2005 study which associated overweight with a lower overall mortality? That study has been widely disputed, though, and is at odds with literally hundreds of others studies showing that overweight and obesity, in and of themselves, increase your risk of developing type 2 diabetes, heart disease, gallbladder disease, sleep apnea, osteoartritis, certain types of cancers and several other serious health problems.

That said, I’m not arguing that the health risks of overweight are necessarily sufficiently compelling that every overweight person should make the choice to live as those in the NWCR do. It’s a huge committment, obviously. I’m just putting this out there because there is a tremendous amount of misinformation surrounding the issue.