By Amitrajeet A. Batabyal
There is no gainsaying the fact that we have an obesity problem in the United States. A disproportionate number of young and old Americans are fat, and many believe that the reason for this insalubrious state of affairs is the large amounts of fast food, soda and candy that Americans consume. Therefore, if overweight Americans would like to lose weight, then they need to curtail their consumption of fast food, soda and candy. This is the conventional wisdom on obesity and its cure.
New research by David Just and Brian Wansink of Cornell University has forcefully challenged this conventional wisdom. These researchers have carefully examined data for a representative sample of the American population that was selected to participate in the Center for Disease Control’s National Health and Nutrition Consumption Survey in 2007-2008. The participants in the survey were divided into eight groups depending on their body mass index (BMI), a measure of body fat.
Interestingly, the analysis conducted shows that if we exclude the clinically underweight and the morbidly obese – who represent about 5 percent of the population – then there is no relationship between the consumption of fast foods, soda and candy and one’s BMI. In other words, about 95 percent of Americans are not fat because they are consuming large quantities of fast food, soda and candy.
This central finding has four significant practical implications. First, since there is no connection between the consumption of seemingly unhealthy foods and BMI for about 95 percent of Americans, policy measures that attempt to tell people in this group that they can lose weight by cutting down on their consumption of these unhealthy foods are likely to be both futile and wasteful.
Second, the inclusion of the small number of chronically underweight and morbidly obese people in previous studies has skewed their findings and, as a result, has led to the above mentioned conventional wisdom about the positive association between the consumption of these foods and BMI.
Third, it is important to comprehend that the Cornell researchers do not claim that consuming fast foods, sodas and candy represent healthy food choices. Instead, a key point of their study is to emphasize that these extravagances receive disproportionate attention relative to their actual impacts.
Finally, policy makers who believe that the way to cure obesity is to ban fast food and soda are both misguided and barking up the wrong tree. To meaningfully attack the obesity problem, it makes more sense to focus on the increasingly sedentary lifestyles of Americans and the fact that they consume insufficient quantities of healthy foods such as fruits and vegetables.
Amitrajeet A. Batabyal is the Arthur J. Gosnell professor of economics at the Rochester Institute of Technology but these views are his own.