December 29, 2003
UW researcher links rising tide of obesity to food prices
Obesity in the United States is in part an economic issue, according to a review paper on the relationship between poverty and obesity published in the January 2004 edition of the American Journal of Clinical Nutrition. The article suggests that the very low cost of energy-dense foods may be linked to rising obesity rates.
The paper is by Dr. Adam Drewnowski, director of the Center for Public Health Nutrition in the University of Washington School of Public Health and Community Medicine, and Dr. S.E. Specter, research nutrition scientist at the U.S. Department of Agriculture Human Nutrition Research Center in Davis, Calif.
“It’s a question of money,” Drewnowski said. “The reason healthier diets are beyond the reach of many people is that such diets cost more. On a per calorie basis, diets composed of whole grains, fish, and fresh vegetables and fruit are far more expensive than refined grains, added sugars and added fats. It’s not a question of being sensible or silly when it comes to food choices, it’s about being limited to those foods that you can afford.”
Energy-dense foods not only provide more calories per unit weight, but can provide more empty calories per unit cost. These foods include French fries, soft drinks, candy, cookies, deep-fried meats and other fatty, sugary and salty items. The review shows that attempting to reduce food spending tends to drive families toward more refined grains, added sugars and added fats. Previous studies have shown that energy-dense foods may fail to trigger physiological satiety mechanisms — the internal signals that enough food has been consumed. These failed signals lead to overeating and overweight. Paradoxically, trying to save money on food may be a factor in the current obesity epidemic.
Many strategies for health promotion over the years have presumed that good nutrition was simply a matter of making the right choices. Drewnowski noted that access to healthier diets could be sharply limited in low-income neighborhoods simply because of the food environment and the nature of the available food supply.
“It is the opposite of choice,” Drewnowski said. “People are not poor by choice and they become obese primarily because they are poor.”
Drewnowski and Specter concluded that continuing to recommend costly foods to low-income families as a public health measure can only generate frustration among the poor and less well-educated. Americans are gaining weight while consuming more added sugars and added fats. They urge that issues of food costs demand attention.
“There is a need for governmental and policy interventions when it comes to the obesity epidemic,” Drewnowski said. “The U.S. Department of Agriculture is addressing this issue with vigor. Government agencies and private foundations have identified childhood obesity as a priority area and are looking for ways to improve nutrition in the schools.”
Obesity in the United States has become a social and economic issue that is resisting conventional medical approaches.
“Genetics and family history can predict whether you will become obese — but then so can your ZIP code,” Drewnowski said. “If poverty and obesity are truly linked, it will be a major challenge to stay poor and thin.”