From: bhjelle@hydra.unm.edu ()
Subject: Re: Adiposity 101
Date: Mon, 04 Jan 93 19:09:07 GMT
Organization: University of New Mexico, Albuquerque

In article <1993Jan4.164932.611@speedy.aero.org> nadel@attatash.aero.org (Miriam Nadel) writes:
>In article <-wrr!tr@lynx.unm.edu> bhjelle@carina.unm.edu writes:
>>With that lead-in, I can't resist being the first to mention
>>the article in the latest New England Journal that shows that
>>obese people who profess to be eating <1200 Cal/day diets
>>in fact eat far more than they report, enough to account
>>for their inability to lose weight. They also exercise some
>>50% less than reported.
>
>I have a couple of quibbles with that study.  First of all, it only involved
>10 people.  If you want to play conflicting studies, there was a study
>some years ago of women who had plateaued on a diet in which they were
>kept in a carefully controlled environment and all intake and output
>measured.  Of the women in the study, some (less than half, but I don't recall
>the numbers) did resume weight loss on the diet, suggesting that they had 
>been underreporting their intake.  The rest, however, continued to remain 
>incapable of further weight loss and 2 even gained weight.

That is compatible with (1) the possibility that the caloric goal
was set too high for some of the subjects, and (2) systematic
errors in measuring caloric intake, as you describe later.
In other words, it is not, as described, in conflict with the NEJM
study.

>Also, the people studied were ones who failed to lose weight while following
>the prescribed diet.  This is pretty rare - most people will lose weight.

But it is this group that has engendered the most argument on this
newsgroup.

[lots of stuff that most would agree with deleted]

>A more serious concern about the recent study to do with interpretation.  
>I heard an interview with the researchers involved in which they were trying
>to be careful not to suggest a character flaw but instead came away sounding
>like the subjects just never registered how much they were eating.  It's

It is truly unfortunate the the researchers have to spend so
much of their efforts worrying about whom they may have offended,
rather than the findings, which are interesting in themselves.

>actually pretty difficult to accurately measure your intake - calorie
>counts on various foods are not precise, scales are not precise, etc..
>A nutritionist shadowing you would be doing well to come within 300 calories
>of a correct number.  
>
>I'm not dismissing the study out of hand - it's an interesting area of
>research.  But I do think that it's very preliminary and subject to
>significant misinterpration.  In particular, the whole issue of why the
>underreporting occurred has really not been approached in any systematic
>way but is instead an area of speculation.  (To be fair, the researchers
>admitted this.)
>
I'm not sure any great insight would follow an inquiry as to
*why* underreporting occurred. An argument that has been
proffered repeatedly here and elsewhere is that there are very
heavy individuals who can fail to lose weight despite very low
calorie diets, even combined with exercise. This study would
suggest that some of that problem has to do with underreporting
caloric intake and exercise.

Brian



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