More than 120 million men and women in China are overweight or obese, according to a new study (Obesity 2007;15:10-18).
The number of overweight men and women may have more than doubled since 1991, and the rates of obesity in men may have more than tripled in the same period.
“Overweight and obesity have become important public health problems in China. There is an urgent need to develop national strategies aimed at the prevention, detection, and treatment of overweight and obesity to reduce the increasing burden of cardiovascular disease,” say the authors from the InterASIA collaborative group.
The authors did a cross sectional survey of a nationally representative sample of 15 540 Chinese adults aged over 35 years. Trained observers measured body weight, height, and waist circumference. Data were also collected on age, education, and lifestyle risk factors.
Results show the prevalence of overweight and obesity were 24.1% and 2.8% in men and 26.1% and 5.0% in women, respectively. The prevalence of central obesity was 16.1% in men and 37.6% in women.
Men aged 45 to 54 years had the highest prevalence of overweight (26%) and obesity (3.1%). In women, 6.2% of those aged 55 to 64 were obese. In each age group, prevalence of obesity was higher for women than for men.
The authors say that applying the results to the Chinese population as a whole indicates that the prevalence of overweight and obesity in the general Chinese adult population is higher than previously reported. In 1991, the prevalence of overweight and obesity were 9.9% and 0.8% in men and 12.9% and 1.9% in women.
“Our study suggests that 119 million Chinese adults aged 35 to 74 years were overweight and 18 million Chinese in the same age range were obese, using BMI [body mass index] criteria. Using waist circumference, 126 million Chinese adults aged 35 to 74 years had central obesity,” they say.
The authors say that other Asian countries have reported similar patterns, which have been associated with a variety of lifestyle and behavioural changes, including physical inactivity and high fat, energy rich diets.
The prevalence of overweight, obesity, and central obesity were higher in people living in urban areas and in people resident in northern China: “Lifestyle factors were the most important risk factors to explain the differences in overweight and central obesity between northern and southern residents.
“Among women, lifestyle and diet were the most important risk factors to explain the differences between urban and rural residents, whereas socio-economic status, lifestyle, and diet were all important among men.”
The InterASIA study was funded by a contractual agreement between Tulane University and Pfizer: “The study was conducted, analysed, and interpreted by the investigators independently of the sponsor.”