Wednesday, June 06, 2007

Repeat after me: Fat is good

An interesting study crossed my desk this week, from a team of researchers in New York who posed the question, "Does percent body fat predict outcome in anorexia nervosa?"

They looked at a number of factors they thought might contribute to relapse in anorexia recovery, including BMI, leptin levels, waist-to-hip ratio, the subtype of anorexia, and percentage of body fat. Only one--body fat--seemed to affect the rate of relapse. "In recently weight-restored women with anorexia nervosa," they wrote, "lower percent body fat was associated with poor long-term outcome."

We're so used to thinking of fat as the Ultimate Evil, which must be banished at any cost, that news like this can feel downright shocking. Fat can be not just good but essential. Without it our brains don't work very well. We're supposed to have a certain amount of fat in our bodies.

This is important for those in recovery from anorexia, especially people (like my own daughter) who are naturally athletic and build a lot of muscle mass. Nothing wrong with muscles, but you've gotta have fat, too. Lean muscle mass without body fat is associated with relapse. And that's not what anybody wants.

So repeat after me: Fat is necessary for human life. Fat is not evil. Fat can even (dare I say it?) be a Very Good Thing.


Carrie Arnold said...


I couldn't read the paper in its entirety, as I don't have a subscription to the journal. However, here's my $.02:

Fat is a living tissue. You don't stuff fat cells like pillows and then leave them there. Fat molecules and other hormones travel in and out of adipose cells all the time. And hormones like leptin and ghrelin (sp?) help regulate food consumption, etc. Thusly, it's not just the fat. It's the good things fat does for us.

Which makes me wonder about another similar study: do people who develop AN lose body fat at a faster rate than those who don't develop AN? The logistics for such a study would be nightmarish, but it would be interesting.


Carrie Arnold said...


I just re-read your article about leptin levels not being correlated with outcome.

::smacks forehead::

Still, it seems that appropriate fat levels seem to indicate a better intake/output of calories.

mary said...

Fat is Good! : )

RioIriri said...

Fat is part of the endocrine system, too. Why are we trying like mad to rid ourselves of an important gland? Would we even think of telling people to get their thyroid glands, pancreas, or thymus removed without a serious medical reason, because they are socially unacceptable? Of course not--that would be stupid.

Now that we know it has important glandular functions, it is irresponsible of medical professionals to recommend dieting.

Harriet said...

And especially since we also know that dieting is a gateway behavior to eating disorders.

Marijuana is illegal, and it kills a lot fewer people. Dieting should be illegal!

Carrie Arnold said...


I'd love to present that bill to Congress- both the drug and obesity lobbiests would have a field day. It'd sure be fun, though!

Actually, I was thinking about the paper about reduced androgen levels in women recovering from AN. My endocrinology is a little (okay, a LOT) rusty, but you've gotta wonder if they're all connected.

Thanks for the article.