A large study of 21,000 randomly selected people in the north east Jilin Province, published in the online journal BMJ Open, found the regular intake of meat and alcohol, having ever been married, and getting less than seven hours sleep a night were all associated with a heightened risk.
Obesity and its health implications is a hot topic in China, with rapid economic growth leading to the adoption of dietary habits and lifestyle choices that are associated with growing levels of obesity in developed nations.
Several recent studies have found the Chinese diet has increasingly become high in fat and energy density, and low in dietary fibre.
The researchers therefore wanted to find out the prevalence of obesity/overweight in a densely populated area of China—Jilin Province has a population of 27m—and uncover trends that might inform future health policy.
All participants completed a detailed questionnaire on lifestyle factors and underwent a physical examination.
More males obese
To take account of the Chinese physique, obesity was classified as a BMI of 28 while overweight was classified as a BMI within the range of 24 to 27.9.
Researchers found that more men than women were overweight and obese.
One in three of the participants (32.3%) were overweight (men 34.3%, women 30.2%) while one in seven (14.6%) were obese (men 16.3%, women 12.8%).
Among men, the prevalence of overweight and obesity peaked at ages 45-54, and at the ages of 55-64 and 65-79 respectively for women.
Risk factors included marriage, with people who had been married at any stage in being 44% more likely to be overweight/obese than those who had never married.
People who drank alcohol regularly were 11% more likely to be overweight/obese than those who never or rarely drank, while those who ate meat regularly were 47% more likely to be overweight/obese than those who ate a predominantly vegetarian diet.
Public health problem
Obesity was also more common among those who slept less than seven hours a night.
While the researchers stressed these findings were restricted to one province, they added: "Overweight and obesity have become a major public health problem in China, although the prevalence of obesity is lower than in developed countries. And there is no doubt that the rapidly increasing occurrence of overweight and obesity in China will continue to increase the prevalence of chronic diseases," they warn.
These findings follow a separate 29-year study of 28,000 students in Shandong province, published in April, which found that 17% of boys and 9% of girls under the age of 19 were obese in 2014, up from 1% for each in 1985.
The study, published in the European Journal of Preventive Cardiology, concluded that China's rapid socioeconomic and nutritional transition had led to an increase in energy intake and a decrease in physical activity.
“This is the worst explosion of childhood and adolescent obesity that I have ever seen," Joep Perk from the European Society of Cardiology told AFP news agency at the time.
Source: BMJ Open 2016
“Prevalence of overweight and obesity and some associated factors among adult residents of northeast China: a cross-sectional study”
Authors: Rui Wang, et al