RÉSUMÉ
Objective: To understand the overweight rate and obesity rate in middle-aged and elderly people in urban area of Beijing, and analyze the changes of body composition and resting metabolic rate with age. Methods: From November 2014 to December 2015, body composition measurement and resting metabolic rate detection were conducted among 858 people aged 51 to 99 years, including 760 men, 98 women, who received physical examination at Beijing Hospital. Results: The overweight rate was 51.4%, and the obesity rate was 16.9%. The overweight rate was 26.5% and the obesity rate was 14.3% in women, significantly lower than those in men (54.6% and 17.2%) (P<0.001). The distribution of skeletal muscle volume, muscle index, body fat percentage, visceral fat area and resting metabolic rate in different age groups were different (P<0.001). In the normal weight group, the skeletal muscle volume, muscle index and resting metabolic rate in age group ≥80 years decreased obviously (P<0.05). At the same time, the body fat percentage and visceral fat area increased obviously (P<0.05). However, the skeletal muscle volume, muscle index and resting metabolic rate of the overweight and obese groups began to decrease obviously in age group 70- years (P<0.05), and the decrease in age group ≥80 years was more obvious. At the same time, body fat percentage and visceral fat area increased significantly in age group 70- years (P<0.05). Conclusion: The overweight and obesity rates were high in the middle-aged and elderly people in the urban area of Beijing, and the rates were higher in men than in women. With the increase of age, the skeletal muscle volume, muscle index and resting metabolic rate gradually decreased, while the percentage of body fat and visceral fat area increased; Overweight and obese people had earlier changes in body composition and resting metabolic rate.