Food assistance programs, particularly the Food Stamp Program, increase food spending and household income. In 2004, adding food stamp benefits to recipients’ incomes raised 9 percent of recipients out of poverty. Nutritional effects of food assistance programs are uncertain.

Americans are increasingly overweight, with the number of obese adults and overweight children doubling between the late 1970s and early 2000s. Several studies of the health consequences of Americans’ weight gain indicate that health care costs and the number of premature deaths...