Dietary fatty acids and insulin secretion:: a population-based study

Objective: Few epidemiological studies have examined the relationship of dietary fatty acids, especially MUFA, with the interrelation between insulin secretion and insulin resistance. We assessed the relation of dietary fatty acids with insulin secretion in a free-living population. Design and setting: This cross-sectional, population-based study was undertaken in Pizarra, a small town in Spain. Subjects and methods: Anthropometrical data were collected for 1226 persons selected randomly from the municipal census, 538 of whom (randomly chosen) were given a prospective, quantitative, 7-day nutritional questionnaire. The fatty acid composition of the serum phospholipids was used as a biological marker of the type of fat consumed. Beta-cell function (beta CFI) and insulin-resistance index (IRI) were estimated by the Homeostasis Model Assessment. Results: To determine which factors influence the variability of the beta CFI, we analyzed the variance of the beta CFI according to sex, the presence of carbohydrate metabolism disorders and the different components of the diet, adjusting the models for age, body mass index (BMI) and IRI. The dietary MUFA and polyunsaturated fatty acids (PUFA) contributed to the variability of the beta CFI, whereas only the proportion of serum phospholipid MUFA, but neither the saturated fatty acids nor the PUFA accounted for part of the variability of the beta CFI in a multiple regression analysis. Conclusion: The results of this population-based study corroborate the results of other clinical and experimental studies suggesting a favorable relationship of MUFA with beta-cell insulin secretion. Sponsorship: Fondo de Investigacion Sanitaria, Junta de Andalucia and the Asociacion Maimonides.