Obesity, a principal health risk, is gaining ground in the US. In a report published in the June issue of the British journal Public Health, two researchers from the US "think tank" RAND found that obesity is associated with higher rates of chronic medical conditions and with worse physical health-related quality of life than are lifetime smoking, problem drinking or poverty. Their study provided new information on major health risks on morbidity and indicated that three out of five adult Americans are either overweight (36 per cent) or obese (23 per cent). According to the researchers more people now are overweight or obese than are, collectively, daily smokers, problem drinkers and below the federal poverty line. "Americans haven't given overweight the same attention as other risks, like smoking, but it is clearly a top health problem and one that is on the rise in all segments of the population. More effective clinical and public health approaches are urgently needed," declare co-authors Roland Sturm, a RAND economist, and Kenneth Wells, a psychiatrist on the RAND staff. Sturm and Wells analysed data from a nationally representative, household telephone survey of 9,585 adults conducted in 1998. The survey included questions covering height, weight, income, smoking and drinking habits and health status. The researchers used the body mass index (BMI), a ratio of height to weight, to define overweight and obesity. They measured health status by analysing responses to questions concerning some 17 major chronic conditions and 12 quality-of-life issues. According to a statement from RAND the US Surgeon General is this year giving top priority to developing a national action plan to reduce obesity's prevalence. It is clearly in his interest to do so.