The occasion went unmarked at the time--no headlines, no speeches, certainly no fruit baskets--but one day, probably in the early 1980s, somebody gained a few pounds and unwittingly made overweight the American norm.
Surveys of the late 1970s found that 47 percent of American adults between 20 and 74 were overweight, defined as having a body mass index of at least 25. (The BMI is a formula based on height and weight.) Nowadays, according to the U.S. Department of Health and Human Services (HHS), a bountiful 65 percent of us are overweight. And the overweight category's obesity subset--those with a BMI of at least 30--has supersized, growing from 15 percent of the adult population in the late 1970s to 31 percent now. Women outnumber men in the healthy-weight category and, oddly, in the obese category; it seems that men cluster in the middle and women at the extremes.
Dieting, or rather the way most people diet, is partly to blame for the nation's corpulence. Dieters can end up consuming more calories than nondieters, according to University of Toronto psychologists C. Peter Herman and Janet Polivy whose paper, "Dieting as an Exercise in Behavioral Economics," is published in the book Time and Decision (Russell Sage). …