Americans More Realistic About Their Diet Quality

The steady upward trajectory in obesity over the past 30 years has brought Americans' dietary habits and attitudes into sharp focus. Research has suggested that Americans view their diets too optimistically, underestimating the amount of calories in their diets, for example, or overestimating the nutritional value. This phenomenon, known as 'optimistic bias,' means some Americans may be less receptive to dietary guidance because they believe that advice must be aimed at someone else.

Recent work by ERS economists suggests that, in recent years, such optimistic bias may be on the wane. Researchers compared how American adults rated the healthfulness of their diets in two national surveys--the 1989-91 Continuing Survey of Food Intakes and the 2005-08 National Health and Nutrition Examination Survey. All survey respondents were asked if they thought their diets were 'Excellent,' 'Very Good,' 'Good,' 'Fair,' or 'Poor' in terms of healthfulness.

Although many things changed about American diets between the survey periods, the overall healthfulness, as measured against USDA dietary guidance, did not. But Americans have become more realistic about diet quality. For men, the probability of rating their diets as excellent or very good fell by 10.5 percentage points; for women, it declined by 8 percentage points. The surveys showed a decline in optimistic ratings across many demographic groups, including respondents who were overweight or obese, those with at least a high school education (but not a college degree), and those living in households with incomes between 130 and 300 percent of the Federal poverty level.

Another striking finding may be of particular interest to nutrition educators. Although it is possible for consumers to choose more healthful foods when they eat out, research shows that food eaten away from home tends to be less nutritious than food prepared at home. Americans seem to recognize this; ERS researchers found that ratings of diet healthfulness were strongly inversely related to the frequency of eating food prepared away from home, particularly fast food. People who rated their diets as poor ate food prepared away from home almost twice as often and ate fast food three times as often as those who rated their diets as excellent.

These results suggest that while Americans' diets are still in need of improvement, consumers understand the relative value of food prepared away from home and, more importantly, may be more receptive to dietary guidance.