Evaluation effects of peanut skin extract on blood glucose regulation and body fat reduction

Peanut skins, a usual by-product in peanut processing industry, is usually discarded as a waste in despite of the high content of phenolic compounds. Polyphenol extract from peanut skins has been demonstrated to inhibit α-amylase activity in vitro. Hence, the aim of this study was to evaluate the regulatory effects of the peanut skin extract (PSE) on blood glucose and body fat by a double-blind, placebo-controlled, clinical study. Subjects with simple obesity (body mass index [BMI] ≥27 or body fat ≥30%) ingested 4 PSE (n = 16) capsules or placebo (n = 14) a day for a total of 6 weeks. Anthropometric measurements (body weight, body fat, blood pressure) and blood biochemical markers including fasting blood glucose (FBG), albumin, total cholesterol (TC), triglyceride (TG), HDL-C, LDL-C, creatinine (Cr), blood urea nitrogen (BUN), AST, ALT were examined every three weeks. Also, 5 subjects were randomly selected for MRI scans to examine the distribution and thickness of abdominal fat layers before and after the trial. The results revealed that after 6-week PSE intake, body weight and body fat decreased 0.33 kg and 2%, respectively. In addition, for the subjects who have abnormal FBG (≥100 mg/dL), their FBG had a significant improvement by 7.4% without changing the levels of other blood biochemical markers after the 6-week PSE supplementation. Therefore, the results demonstrated that PSE has positive effects on blood glucose and body fat regulations.