The percentage of overweight Americans has increased in recent decades. Despite many possible reasons for the increase in obesity cases, the root cause is essentially a greater overall energy intake than energy expenditure.
One reason for obesity prevalence in the U.S. may be larger food portion sizes, especially outside of the home, which encourage individuals to eat more calories.
Portion sizes for popular take-out restaurants, fast-food chains, and family restaurants were measured and compared to U.S. Department of Agriculture (USDA) and Food and Drug Administration (FDA) standards, and to portion sizes in the past. Information was obtained from portion weights, package labels, and manufacturer claims. Below are the findings of the study, which appeared in the American Journal of Public Health:
- Excluding white bread, all commonly available food portions exceeded USDA and FDA standards. The largest excesses occurred in cookies (700% over USDA suggestion size), pasta (480%), and muffins (333%).
- Portion sizes for foods such as hamburgers, French fries, and soda were two to five times larger in the study than in the past.
- Portion sizes started to increase in the 1970s, grew dramatically in the 1980s, and currently continue to rise parallel to increases in average American body weights.
Food manufacturers and restaurants have little incentive to reduce portion sizes: Profits for these companies rise when product size is increased. Also, a recent survey showed that Americans ignore portion sizes when attempting to follow a healthy diet. As portion sizes at restaurants increase, realize that despite what your parents taught you, you don't always have to clean your plate.
Young LR, Nestle M. The contribution of expanding portion sizes to the U.S. obesity epidemic. American Journal of Public Health 2002:92(2), pp. 246-249.
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