Comparison of the effects of two diets (low-glycemic index and low-fat) on weight loss, body mass index, glucose and insulin levels in the obese women

In recent years reducing the dietary glycemic index has been proposed as a novel approach to weight-loss and prevention of metabolic diseases (type 2 diabetes and cardiovascular diseases). The aim of the present study was to determine the effect of low-glycemic index diet and Low-fat diet on weight-loss, body mass index, fasting and post-prandial glucose and insulin levels in the obese women. In this clinical- trial study 46 obese women aged 18 to 55 years -with BMI ≥27 who had referred to Motahary clinic in Shiraz, Iran, were randomly divided into two equal groups, each with a specific diet (i.e. low fat and low glycemic index) which continued for a period of six weeks. Body weight, BMI, fasting and post-prandial glucose and insulin level of the patients were measured at the beginning and at the end of the period. The obtained data was analysed by means of SPSS statistical software, sample paired-t and sample independent-t at the significant level P<0.05. Mean age of the subjects was 37.9±7.6 years. The variables under study significantly decreased in both groups six weeks after dietary treatment (P<0.05). Mean insulin level in the low fat diet group statistically decreased compared with low GI group (P=0.02). However, regarding other variables no difference was observed between treatment effects in the two groups. Both diets can equally be effective in weight loss, BMI, and glucose concentration level, Additional studies are required to examine the relationship between low fat, low glycemic diets and insulin level in the obese women.