[The trends of body mass index and overweight in population aged 25 - 64 in Beijing during 1984 - 1999].

Objective: To analyse the trends of body mass index (BMI) and overweight in a population aged 25 through 64 years in Beijing.

Method: During 1984 to 1999, five cross-sectional surveys on cardiovascular disease (CVD) risk factors were carried out in the CVD monitoring population in Beijing. The mean levels and trends of BMI as well overweight in different sexs, age groups and areas were analysed.

Results: (1) In the period of 1984 to 1999, the mean BMI increased from 23.3 to 24.0 (kg/m(2)) in population aged 25 to 64 years, and overweight increased from 27.5% to 35.9%. (2) From 1984 to 1999, the prevalence of overweight increased from 23.5% to 43.3% in males. This increasing trend was seen in both urban and rural populations and in all age groups. Prevalence of overweight decreased from 36.0% to 23.3% in urban females, but increased from 28.4% to 46.0% in rural females. (3) From 1984 to 1999, prevalence of overweight increased from 29.1% to 31.8% in urban population, while 22.1% to 49.6% in rural population. BMI and prevalence of overweight were higher in urban than in rural (P < 0.05) in 1984 to 1985 but the levels in rural were approaching and exceeding the levels in urban (P < 0.05) in 1999.

Conclusion: Trends of BMI and overweight increased in the urban males and both males and females in the rural, while the increase of both BMI and overweight was seen more rapid in rural than in urban.