Examining food security and obesity in America.

This week, the U.S. Department of Agriculture (USDA) released its annual report on household food security in the United States. According to USDA, some 12.5 million households, or roughly 11 percent of all households, experienced "household food insecurity" at some point in 2006 and some 35 million people lived in households with some form of food insecurity. Most of these households were low income. The report showed little change in food security levels in the U.S. over the last decade.

While these numbers sound ominous, it is important to understand what "food insecurity" means. According to the USDA, "food insecurity" is usually a recurring and episodic problem rather than a chronic condition. In 2006, around two-thirds of food insecure households experienced "low food security," meaning that these households managed to avoid any disruption or reduction in food intake throughout the year but were forced by financial pressures to reduce "variety in their diets" or rely on a "few basic foods" at various times in the year. According to the USDA, the remaining one-third of food insecure households (around 4 percent of all households) experienced "very low food security," meaning that at least once in the year their actual intake of food was reduced due to a lack of funds for food purchase. At the extreme, about 1.4 percent of all adults in the U.S. went an entire day without eating at least once during 2006 due to lack of funds for food.

Children are generally shielded from food insecurity. Around one child in two hundred experienced "very low food security" and reduced food intake at least one time during 2006. One child in a thousand went a whole day without eating at least once during the year because the family lacked funds for food.

Political advocates proclaim that the USDA reports suggest there is widespread chronic hunger in the U.S. But the USDA clearly and specifically does not identify food insecurity with the more intense condition of "hunger," which it defines as "discomfort, illness, weakness, or pain...caused by prolonged involuntary lack of food."

What is rarely discussed is that the government's own data show that the overwhelming majority of food insecure adults are, like most adult Americans, overweight or obese. Among adult males experiencing food insecurity, fully 70 percent are overweight or obese. Nearly three quarters of adult women experiencing food insecurity are either overweight or obese, and nearly half (45 percent) are obese. Virtually no food insecure adults are underweight.

Food insecure men are slightly less likely to be overweight or obese than men who are food secure (70 percent compared to 75 percent). But food insecure women are actually more likely to be obese or overweight than are women who are food secure (73 percent compared to 64 percent).

Thus, the government's own data show that, even though they may have brief episodes of reduced food intake, most adults in food insecure households actually consume too much, not too little, food. To improve health, policies must be devised to encourage these individuals to avoid chronic over-consumption of calories and to spread their food intake more evenly over the course of each month to avoid episodic shortfalls.

Yet most proposed policy responses to food insecurity call for giving low-income persons more money to purchase food despite the fact that most low-income persons, like most Americans, already eat too much. Such policies are likely to make the current situation worse, not better. One commonly proposed policy, for example, is to expand participation in the Food Stamp program. Participation in the Food Stamp program, however, does not appear to reduce food insecurity. Households receiving food stamps do not have improved food security compared to similar households with the same non-food stamp income who do not participate in the program. Moreover, participation in the Food Stamp program does not appear to increase diet quality. Compared to similar households who do not receive food stamps but have the same non-food stamp income, households receiving food stamps do not consume more fruits and vegetables but do, unfortunately, consume more added sugars and fats.

While the Food Stamp program has little positive effect on food quality, considerable evidence indicates that the program has the counterproductive effect of increasing obesity. For example, a recent study funded by USDA found that low-income women who participate in the Food Stamp program are substantially more likely to be obese than women in households with the same non-food stamp income who did not receive food stamps. Over the long term, food stamp receipt was found to increase obesity in men as well. While other research has failed to confirm this link between food stamps and obesity, the possibility that this program has harmful effects remains quite real.

Developing a rational policy on nutrition and poor Americans will require dispelling common misconceptions concerning poverty and obesity. For example, one common misconception is that poor people become obese because they are forced, due to a lack of financial resources, to eat too many junk foods that are high in fat and added sugar. According to this theory, poor persons struggle to obtain sufficient calories to maintain themselves and are forced to rely on junk foods as the cheapest source of calories, but because junk foods have high "energy density" (more calories per ounce of food content), these foods paradoxically induce a tendency to overeat and thereby cause weight gain.

One problem with this theory is that junk foods are not a particularly cheap source of calories. For example, soft drinks are high in added sugar and are generally associated with weight gain, but as a source of calories, brand name soft drinks such as Coca-Cola and Pepsi are often more expensive (in terms of calories per dollar) than milk. Snack foods such as potato chips and donuts cost two to five times more per calorie than healthier staples such as beans, rice, and pasta. Families truly seeking to maximize calories per dollar of food expenditure would focus not on junk and snack foods but on traditional low-cost staples such as beans, rice, flour, pasta, and milk. These foods are not only less expensive but actually have below-average energy density and therefore a lower potential to promote weight gain.

In reality, poor people are increasingly becoming overweight for the same reason that most Americans are becoming overweight: They eat too much and exercise too little. Like the rest of America, the poor eat too many high-fat foods and foods with added sugars, but they do this for the same reason the average American over-consumes these foods: They are highly palatable. While it would be desirable for poor people (like all Americans) to drink fewer soft drinks and eat more broccoli, simply expanding the Food Stamp program would not accomplish that goal. What is required is a very difficult effort to change food preferences.

Contrary to the claims of poverty advocates, the major dietary problem facing poor Americans is too much, not too little, food. Public policies should be directed toward encouraging the poor to avoid chronic over-consumption, exercise more, and reduce intake of foods rich in fat and added sugar.

Robert Rector is senior research fellow in domestic policy studies at the Heritage Foundation.