Saturday, August 25, 2007

another look at Rethinking Thin

I finally read through all of Gina Kolata's Rethinking Thin: The Science of Weight Loss -- And the Myths and Realities of Diets. The book was a real eye-opener. I had skimmed some of it, read some articles about it, and even have written about it here before. But actually reading through the whole book, a few things really struck me.

The first is that there are no new diets under the sun. Though we have a sense of the 1800s as a time when fat was all the rage -- actress Lillian Russell was considered a sex symbol at 200+ pounds -- many people still dieted. Though the beauty ideals were heavier than they are now, some people still had trouble maintaining a fashionable weight. There was a low carbohydrate diet that was, essentially, the same as Atkins' "New Diet Revolution." There were high-carbohydrate, low-fat diets. There were even low-protein diets -- which is the only one that hasn't seemed to have been resurrected lately. Maybe that's next. And just like now, there were hucksters who sold questionable and even dangerous substances to desperate people who wanted to lose weight.

The next thing that hits you like a ton of diet books is that with 200 years of dieting under our collective belts, we haven't really made much progress. The only thing that has really gotten thinner is our beauty ideals, especially for women. A study of Miss America data from the 1920s is revealing. The winners got taller, but their weights got lower.

In the 1920s, contest winners had body mass indexes that ranged from 20 to 25, slender but well within the range that is deemed a healthy range...More recently, some Miss America winners have body mass indexes as low as 16.9...The more relaxed male standard for fatness is seen in Brad Pitt, Jennifer Aniston's former husband anda model for male attractiveness. He is reportedly 6 feet tall and weighs 159 pounds. That gives hima body mass index of 21.6, healthy according to federal standards. If Brad Pitt had the same body mass index as Jennifer Aniston, 18.3, he would weigh only 135 pounds.
I'm not sure what Virginia Beckham or Paris Hilton's BMIs are, but I'm sure they're lower than Jennifer Aniston's. We are entering an era where the ideal body type for women is extremely underweight, something that statistics show is much more dangerous than being overweight, according to Kolata's research. This means that people who are in a healthy BMI range are still trying to lose weight to meet the underweight ideal.

Kolata's analysis of statistical studies demonstrates the difficulty of anyone losing weight beyond a certain genetically determined range. Twin studies and studies of adopted children show that genetics trump environment. Identical twins raised apart have very similar weights, and adopted children have weights closer to those of their biological parents than those of their adoptive ones. This is the part of the book that many people found discouraging. She also presents the radical idea that no one really knows if losing weight has the same health benefit as never being fat at all. People (and rats) who lose a lot of weight have a metabolism more like someone who is starving than that of someone who has always been thin.

The thing that I think Kolata fails to emphasize enough is that people aren't rats. I don't disagree with her basic ideas, but weight loss is very difficult to study because of the complexity of the human mind. It's also rare that a weight-loss study lasts more than a year or two, because of practical considerations.

Kolata focuses on hunger and metabolism as powerful drives that regulate body size. A lot of us, for various reasons, are eating for reasons other than hunger. I know I'm not the only person who has eaten dessert after Thanksgiving dinner, for example, even though my belly already felt like it might burst. I also find myself eating when I'm bored, lonely, angry, frustrated, or having fun with friends. Maybe instead of statistical studies, researchers should talk to dieters and find out what is really going on when they're eating.

There is no doubt that environmental factors also play a role. Food is also much more available than ever before, and in larger quantities. I was struck when shopping at the Home Depot by how many carts had empty soda bottles and candy wrappers in them. It made me wonder how we became a society where people thought they needed a snack while they shopped for caulk and staple guns. Sure, the store is huge, but I think I can cross it without provisions!

My personal theory is that as the beauty ideals get more impossible to maintain, more people label themselves "fat" and start acting in ways they think a fat person does. We have such all-or-nothing ideas about food -- as illustrated by "Fat March," where the trainers berated contestants who "splurged" on half a slice of pizza after a long day of marching. We're either dieting or blowing it. So, since most of us don't want to commit to a diet of dry grilled chicken breasts and steamed broccoli day after day, we decide we might as well supersize our fries. The ideals are unreachable, so why even try?

When I'm queen of the world, which I am sure is going to happen any day now, people would be treated with respect no matter what their size. People would live in communities where daily activity was fun and easy -- you could walk to the movies, work, or even the ice cream shop. There would be lots of parks and playgrounds and less four-lane roads. There would be bike trails that connected residential neighborhoods to schools and workplaces. Kids would go to small, high-quality schools where there was plenty of time for play and they served a wide range of food choices in the cafeteria. Restaurants would emphasize quality and variety over portion sizes. Fresh fruits and vegetables, not corn and soybeans, would be subsidized by the government. There would be universal health care and the standard workweek would be thirty hours. People would have lots of time to spend with their families and friends.

Would all of this stuff make people thinner? Who knows? Who cares? I think it would make them happier, and that's really the point, isn't it?


  1. I wish there were more posts on blogs on this topic! I have this theory that people put on weight because they are around people who are big. I believe this mechanism will continue for at least the next 50 years. I see it when I am at university, where people are young and thin. You feel like being thinner. Then you go to a meeting of middle aged people and you can't help but eat the creme cakes afterwards, because you are thinner then everyone else and 'it's ok for that reason'.

    I am following the progress of about 18 weight loss blogs, and the average weight loss over 3 months has been 44 grams per week. Something is stopping people from losing weight but the question is what is it?

    The whole motivation issue is a complex one, you might like to read more on this, The Motivated mind by Raj Persaud contains a lot of interesting research about why people do certain things.

  2. Interesting stuff. It really is all so complex. Guess that's why we're all out here, trying to still make it work.

  3. I will vote for you for queen of the world.

    I totally agree with you about the all or nothing issue too. I think that's a huge part of the problem and you don't hear people talk about it that much.


"Count your calories, work out when you can, and try to be good to yourself. All the rest is bulls**t." -- Jillian Michaels at BlogHer '07