Relation of habitual diet to fasting plasma insulin concentration and the insulin response to oral glucose.

Blood glucose and plasma insulin levels during a 50 g oral glucose tolerance test were measured in a population sample of 220 people (109 men; 111 women), who also earlier recorded their diet over a 2-d period. In the men, but not the women, there was a statistically significant inverse relationship between total daily energy intake and both fasting and post-load plasma insulin concentrations. This correlation, which was independent of the degree of adiposity, may be a confounding factor in epidemiological studies relating plasma insulin levels to subsequent coronary heart disease.