In Korean Women, High Plasma Level of Enterolactone Reduces Risk of Type 2 Diabetes and This Effect is Enhanced in Equol-Producers

Abstract

Diabetes, if left untreated, can cause many health complications. Type 2 diabetes is known to be primarily due to lifestyle and thus, efforts have been made to reduce its risk by diet particularly of vegetables containing various antioxidants. In the present study, this possibility was investigated by examining association between the plasma level of enterolactone, a metabolite of food lignans and the risk of type 2 diabetes and the association was compared between producers and non-producers of equol, a metabolite of soy isoflavone. The study population was composed of 693 cases and 698 matched controls within the Korean Genome Epidemiology Study. Logistic regression models were used to compute the odds ratio (OR) and 95% confidence intervals (CI). Stratified analysis was done to examine the association between plasma enterolactone concentration and risk of type 2 diabetes, and then, this association was examined in terms of sex and status of equol producing ability. In female, compared with the reference level, a marginally significant risk reduction was found at the highest concentration of enterolactone (for the highest category: OR, 0.68; 95% CI, 0.46–1.01). In equol producers among women, the highest concentration of enterolactone significantly decreased the risk of type 2 diabetes (OR, 0.58; 95% CI, 0.34–0.96). In equol non-producers among women, however, the concentration of enterolactone was not associated with the risk of type 2 diabetes. In male, enterolactone concentration was not associated with risk of type 2 diabetes regardless of equol producing status. In conclusion, high plasma concentrations of enterolactone were associated with a decreased risk of type 2 diabetes particularly, in equol producing female.