An investigation was undertaken in Northeast Thailand, a country undergoing rapid health transition, to find out whether there is a likelihood that the nutritional and lipid pattern of an adult population in Northeast Thailand is related to coronary heart disease in the same way as in western countries. In a cross-sectional study, the body mass index (BMI) and the waist-hip ratio as well as the important plasma lipids were determined. The nutritional status and the lipid profile of the predominantly middle-aged population is characterised by a generally favourable nutritional status and lipid concentrations, where the distribution, indicated by the medians, of the relevant variables over the total population is concerned. A rather high proportion of individuals was found to be overnourished and to have high triglyceride levels. Individuals with high triglyceride levels run a risk of developing coronary heart disease only when the LDL-HDL fraction is above 5. Only 3% of the total population investigated had a LDL-HDL ratio above that value. Since hypertriglyceridaemia is also linked to the insulin-resistant syndrome, it is concluded that, if the mortality of coronary heart disease increases in future, then this must be accounted probably more to the after-effects of the insulin-resistant syndrome than to the direct effect of an atherogenic lipid pattern. This view is supported by a high prevalence of impaired glucose tolerance (IGT) and non-insulin dependent diabetes mellitus (NIDDM) in the population under survey. Preventive measures in the area should concentrate among others on reducing overnutrition, especially among women, and increasing physical activity and screening for NIDDM.