A high isoflavone diet does not change glucose tolerance, body weight, or body fat accumulation in Wistar rats (LB424)

Abstract

Obesity is associated with increased risk of developing insulin resistance, inflammation, heart disease, and cancer. The accumulation of fat can be influenced by a variety of factors, including diet and activity. There is evidence that soy isoflavones may prevent fat gain by increasing thermogenesis. We hypothesized that rats fed a high isoflavone (HIF) diet would have decreased fat accumulation and improved basal glucose tolerance compared to animals fed a low isoflavone (LIF) control diet. Male Wistar rats were fed a low isoflavone control diet (LIF) diet for 72 days. Intraperitoneal glucose tolerance tests were performed, and body fat percentage was determined via Dual‐energy X‐ray absorptiometry (DXA). There were no differences in body weight (p=0.125), body fat percentage (p=0.218), fat pad weight as a percentage of body weight, or glucose tolerance area under the curve (AUC) (p=0.401). These findings suggest that the effects of an HIF diet may be strain‐dependent. Moreover, a metabolic challenge such as a high fat diet may be necessary to see differences in fat accumulation that has been reported in other rat strains.