HIGH SATURATED FAT AND LOW STARCH AND FIBER ARE ASSOCIATED WITH HYPERINSULINEMIA IN A NONDIABETIC POPULATION - THE SAN-LUIS VALLEY DIABETESSTUDY

A geographically based sample of 1069 Hispanic and non-Hispanic white persons aged 20-74 years, living in southern Colorado and who tested n ormal on an oral glucose tolerance test (World Health Organization cri teria) were evaluated to determine associations of dietary factors wit h fasting serum insulin concentrations. Subjects were seen for up to t hree visits from 1984 to 1992. A 24-h diet recall and fasting insulin concentrations were collected at all visits. In longitudinal data anal ysis, lower age, female gender. Hispanic ethnicity higher body mass in dex, higher waist circumference, and no vigorous activity were signifi cantly related to higher fasting insulin concentrations. High total an d saturated fat intake were associated with higher fasting insulin con centrations after adjusting for age, sex, ethnicity, body mass index, waist circumference, total energy intake and physical activity. Dietar y fibre and starch intake were inversely associated with fasting insul in concentrations. No associations with fasting insulin concentrations were observed for monounsaturated fat, polyunsaturated fat, sucrose, glucose and fructose intake. Associations were similar in men and wome n and for active and inactive subjects though associations of fibre an d starch intake with insulin concentrations were strongest in lean sub jects. These findings support animal studies and a limited number of h uman population studies which have suggested that increased saturated and total fat intake and decreased fibre and starch intake increase fa sting, insulin concentrations and may also increase insulin resistance . These findings, which relate habitual macronutrient consumption to h yperinsulinaemia in a large population, may have implications for stud ies attempting primary prevention of non-insulin-dependent diabetes me llitus.