Studying obesity in the Asia–Pacific region is difficult because of the diverse ethnic background and different stages of economic and nutrition transition. The burden of cardiovascular disease associated with overweight (defined as body mass index ?25?kg?m?2) was previously estimated for countries within the region. However, using the conventional cut?point of 25?kg?m?2 ignores the continuous association between body mass index and cardiovascular disease from approximately 20?kg?m?2. By estimating the proportion of cardiovascular disease that would be prevented if the theoretical mean body mass index in the population was shifted to 21?kg?m?2, nationally representative data from 15 countries suggested the population attributable fractions for cardiovascular disease were approximately three times higher than the previous estimates. Coronary heart disease attributable to body mass index other than 21?kg?m?2 ranged from 2% in India to 58% in American Samoa. Similarly, the population attributable fraction for ischaemic stroke ranged from 3% in India to 64% in American Samoa. If cardiovascular risk increases from 21?kg?m?2 applies to all populations, most countries in the region will need to aim towards substantially reducing their current population mean body mass index in order to lower the burden of cardiovascular disease associated with excess weight.