Trends and dietary determinants of overweight and obesity in a multiethnic population.

OBJECTIVES: To describe trends in BMI among different ethnic groups in Hawaii and to explore the relation of nutrient and food intake with excess weight. RESEARCH METHODS AND PROCEDURES: We pooled demographic, anthropometric, and nutritional data derived from a detailed diet history for 159,683 participants of 18 population-based epidemiological studies conducted in Hawaii over a 25-year period. The age-adjusted prevalence of excess weight (BMI > or = 25 kg/m(2)) was estimated for 5-year intervals. To explore dietary determinants of excess weight, we computed odds ratios using logistic regression. RESULTS: During the study period, the prevalence of excess weight increased considerably among all ethnic groups. Native Hawaiians had the highest and Asian Americans had the lowest prevalence of excess weight at all times. Although the percentage of calories consumed from carbohydrates increased, the percentage of calories from fat decreased over time. On an individual level, fat and protein consumption predicted a higher BMI, and dietary fiber intake predicted a lower BMI. Similarly, a higher consumption of meat, poultry, and fish was related to excess weight, whereas fruit and vegetable intake were inversely associated with excess weight. After stratification by ethnicity, the associations were not materially altered among women, but carbohydrates seemed to have a stronger association with excess weight among Native Hawaiian and Japanese men than among white men. DISCUSSION: In this large ethnically diverse population, plant-based foods and dietary fiber emerged as a potential protective factor against excess weight regardless of ethnicity.