Subscribe Editor's Note Search the Magazine |
Taubes’ story rankled many nutrition scientists, including Caballero, a member of the Institute of Medicine's Food and Nutrition Board. The scientific panel defines the nutritional requirements of a healthy diet (which have included the Recommended Dietary Allowances, and the expanded version of the RDAs known as the Dietary Reference Intakes, or DRIs). Many health and agricultural institutions, from the Food and Drug Administration to the American Heart Association, rely upon the Board’s scientific reports to formulate their policies. Caballero calls Taubes’ piece a “huge oversimplification.” True, the percentage of fat in the American diet has gradually fallen for several decades, and obesity has risen. But coincidence does not prove causation; no hard evidence shows that one contributed to the other. Says Caballero, “A greater number of low-fat products in the grocery stores can’t be extrapolated to mean a decrease in consumption of fat in the population.” In the period between 1987/88 and 1994/96, the percentage of fat in the American diet did fall—from 36 percent to 33 percent, according to USDA surveys—“hardly earth-shattering,” says Caballero. And percentages tell only part of the story because Americans also increased their total consumption of calories. So while the percentage of fat in the diet declined relative to carbohydrates, people appear to be consuming more total fat than they did before. So what is making people fat? Caballero believes that degradation of the American diet is partly to blame. The trend toward the super size—in which a typical fast-food meal has grown from a one-ounce burger and eight-ounce soft drink to a six-ounce burger and a 64-ounce soda in the past 40 years—has not helped. Americans’ love affair with soft drinks also troubles Caballero. Daily soda consumption increased 74 percent in teenage boys and 65 percent in teenage girls between 1977/79 and 1994. Americans now consume more soda than milk. Research suggests that children who drink a lot of soda are more likely to be obese than children who drink little or none. All told, Americans ate 148 calories more per day by the mid-1990s than they did in the mid-1970s. That might seem like a lot, but Caballero believes another trend is more pernicious: the sharp decline in physical activity. “We’ve become a passive, automatic society,” he says. “Now, 74 percent of the population doesn’t have the minimum physical activity recommended by the CDC: 30 minutes per day,” Caballero exclaims. “And of those 74 percent, 30 percent don’t do anything!” Many factors indicate that Americans are becoming more sedentary. High school students who participated in daily physical education classes dropped from 42 percent in 1991 to 29 percent in 1999, according to the CDC. Nielsen data show American families watched 36 more minutes of TV per day in 1999 than they did in 1982. And studies by Johns Hopkins School of Medicine researcher Ross Andersen suggest children’s programming—in which 60 percent of the ads are for food—has another insidious effect: prompting children to eat and eat.
The answer then, is simple, at least according to some observers. Overweight people simply need to eat less and exercise more. They should have the fortitude to resist that Whopper, and take personal responsibility for losing weight and keeping it off. In advertising parlance, they should just do it! |
After analyzing the results of a CDC survey called