Overweight? "Rethinking Thin" explains it could be the genes, not the fridge

"Rethinking Thin:

The New Science of Weight Loss — and the Myths and Realities of Dieting"

by Gina Kolata

Farrar, Straus and Giroux, 257 pp., $24

As a science journalist, Gina Kolata of The New York Times is accustomed to making readers angry. In her daily reporting and her book writing, she has revealed controversial truths about sex, infectious diseases, cloning, exercise and many other emotionally charged topics.

In her new book, "Rethinking Thin," Kolata reaches conclusions quite likely to make enemies of every diet marketer alive. The diet marketers will probably find allies in the millions of thin Americans who find overweight Americans disgusting.

Her first conclusion is straightforward: Diets almost never lead to better health for those who try them. Not the Atkins diet or the South Beach diet or Weight Watchers or Jenny Craig. In fact, most diets fail to permanently reduce the poundage of most users.

The second conclusion is less straightforward, because the human body is an extremely complicated mechanism. But here it is: Overweight women and men are rarely that way because they lack willpower near the home refrigerator and in restaurants. Instead, they are overweight primarily because of the genes they inherited. Phrased differently, so that condemnatory thin people can understand, thin women and men are rarely that way because they possess willpower near the home refrigerator and in restaurants. Instead, they are thin primarily because of the genes they inherited.

Weight as destiny

The research is overwhelming, Kolata says: Fat people find it difficult to lose lots of weight permanently, just as thin people find it difficult to gain lots of weight permanently. In a way, weight is like height. A girl baby with her parents' genes who is well fed as an infant might end up 5 feet 6 inches tall rather than the 5 feet 4 inches of her mother. But it would be extremely unusual for that girl to end up at 6 feet tall. Even if she wants to end up at 6 feet, there is nothing practical she can do to reach even 5 feet 7 inches.

Because feelings about diets and obesity are inextricably linked to the body image of the individual doing the thinking, it is significant to know that Kolata is thin and always has been. She is not interpreting the scientific evidence to rationalize her obesity.

It may also be worthwhile to disclose physical data about the reviewer. At age 30, I had reached 6 feet in height and weighed about 150 pounds. Thin. Now, almost 60, I am the same height, but weigh about 250 pounds. Overweight. Obese, even, by many measures.

Yet I play tennis and baseball regularly, ride my bicycle or walk everywhere I go week after week, climb up and down steps all day and much of the night without getting winded, score well in my check-ups at the medical clinic. I dislike the way I look, to be sure, so Kolata's book is balm to me.

Studies and stories

Kolata is a first-rate author. She constructs the narrative along two alternating tracks. One track, consisting of eight chapters, covers the research of scientists across the United States and, to some extent, across the globe. Some of those scientists are studying fat cells. Some of those scientists are studying brain cells.

Some of those scientists are mounting statistically significant, long-term research studies, as they compare, for example, individuals on the low-carbohydrate Atkins diet against individuals on a less gimmicky count-your-calories-every meal diet.

The second track, consisting of seven interludes, follows the individuals who agree to participate in a carefully controlled weight-loss study at the University of Pennsylvania. The researchers will randomly place half of the volunteers on the Atkins diet, the other half on the count-your-calories diet.

Memorable accounts

It is those individuals whose sagas are most likely to remain seared in readers' brains at the end of Kolata's book, individuals like Carmen J. Pirollo, a Philadelphia-area schoolteacher.

At the beginning of the two-year study, he stands 5 feet 11 inches and weighs 265 pounds. During the two years, he loses significant weight.

Does he regain that weight? Readers who care about the searing obesity debate being carried on every day across the United States will want to read Kolata's book to find out.