OBJECTIVESTo compare changes in body mass index (BMI), prevalence of over weight and obesity of the population in a community cohort of Peking University during 1992 to 2002, and to study their characteristics of individual BMI.

METHODSTotally, 1 985 individuals aged 35-64 years were selected from Peking University community with stratified random sampling method for baseline survey by physical examinations and questionnaire interviews to collect relevant data in 1992. And, a follow-up survey was conducted for each individual of the cohort in 2002. Data were analyzed for 1 437 individuals with complete records of the two surveys.

RESULTS(1) In the period from 1992 to 2002, weight increased averagely 4.89 kg in men and 3.08 kg in women, respectively, and BMI increased to 25.22 kg/m2 in 2002 from 23.49 kg/m2 ten years ago in men and to 25.02 kg/m2 from 23.30 kg/m2 in women. (2) Prevalence of overweight increased by 47.8% in men and 29.5% in women, and prevalence of obesity increased by 124.2% in men and 131.3% in women, respectively. (3) 74.9% of men with overweight ten years ago remained overweight and 22.9% of them became obese in 2002. 85.7% of men with obesity ten years ago remained obese in 2002. 58.2% of women with overweight ten years ago remained overweight and 34.5% of them became obese in 2002. 93.7% of women with obesity ten years ago remained obese in 2002.

CONCLUSIONSMean BMI and prevalence of overweight and obesity of population in Peking University community increased during 1992 to 2002. Most of those with overweight or obesity ten years ago remained overweight or obese and few of them became normally weighed ten years later. Those with overweight BMI were more liable to become obese than those with normal BMI. All these results indicated once overweight or obesity established, it was difficult to be reversed. Therefore, the key to control overweight and obesity rests on its earlier prevention.