The 2010 Dietary Guidelines for Americans recommend that adults and children should eat a variety of fruits and vegetables to help them achieve and maintain a healthy weight. In this study, Bertoia and colleagues examined associations between changes in the intake of specific fruits and vegetables recorded in dietary questionnaires and self-reported weight changes in 133,468 US men and women followed for up to 24 years in the Nurses’ Health Study, Health Professionals Follow-up Study and Nurses’ Health Study II. After adjusting for self-reported changes in other lifestyle factors such as smoking status and physical activity, an increased intake of fruits and of several vegetables was inversely associated with 4-y weight change (-0.53 lb (- 0.24 kg) for each extra daily serving of fruit, -0.25 lb (-0.11 kg) for vegetables). However, starchy vegetables, for example peas (1.13 lb; 95% CI 0.37 to 1.89 lb) and corn (2.04 lb; 95% CI 0.94 to 3.15 lb), were associated with weight gain.
These findings may not be generalizable–nearly all the participants were well-educated white adults, and the use of dietary questionnaires and self-reported weight measurement may have introduced measurement errors. However, study strengths include a very large sample size and long follow-up, with consistent results across three cohorts. The authors state, “our findings support benefits of increased fruit and vegetable consumption for preventing long-term weight gain and provide further food-specific guidance for the prevention of obesity, a primary risk factor for type 2 diabetes, cardiovascular diseases, cancers, and many other health conditions.”