Prevalence of underweight, overweight and obesity in urban Hanoi, Vietnam.

This study aims to assess the prevalence of underweight, overweight and obesity among adults in urban Hanoi, Vietnam; and compare these results to previous estimates among adults in urban Ho Chi Minh City. Survey participants were residents in urban Hanoi, Vietnam and aged between 25-74 years. Data from a cross-sectional biomedical survey conducted in 2004 were collected; which included a questionnaire, physical examination and blood tests. The age-standardised prevalence of overweight and obesity in 2004, using Asian-specific body mass index cut-offs, were 28.6% and 2.1%, respectively. The prevalence of overweight/obesity (combined) was similar in males (29.7%) and females (31.5%), and generally increased with age. The prevalence of overweight/obesity was considerably lower if the standard cut-off values of the World Health Organization were used. The age-standardised prevalence of underweight was 13.3%; and that of 'increased risk'/'substantially increased risk' waist circumference (combined) was 27.9% in males and 25.7% in females, respectively. Almost one in three adults in urban Hanoi were overweight or obese in 2004 and more than one in ten were underweight (based on Asian-specific cut-off values). This prevalence of overweight/obesity is similar to that for adults in urban Ho Chi Minh City, but the prevalence of underweight is lower. While low body weight remains a concern, overweight and obesity are an increasing problem for urban Vietnamese adults.