Clinical Study of Astaxanthin on Glucose Tolerance in Nondiabetic Subjects

Astaxanthin (ASTX) is a xanthophyll carotenoid produced by Haemococcus pluvialis, and is found in microalgae, plankton, krill and other seafood. ASTX has strong antioxidant activity, which is an attractive nutraceutical for further investigation in diabetes, lipid profile, and atherosclerotic cardiovascular disease where antioxidant cellular protection may be of clinical benefit. We already reported the effects of astaxanthin (randomized, double-blind, placebo-controlled study) on glucose metabolism and lipid profile in 44 healthy volunteers in the 10th Asia Pacific Conference on Clinical Nutrition 2017. Here we report the effects of ASTX on glucose metabolism in 29 subjects whose HbA1c was from 5.6 % to 6.4 % at baseline. Data of 75g OGTT and HbA1c in 29 subjects (16 in ASTX group and 13 in Placebo group) were analyzed. After ASTX (12mg/day) supplementation for 12 weeks, the glucose level at 30 min by 75g OGTT was significantly decreased compared to before. The level of HbA1c was also significantly decreased compared to before. Furthermore, we assessed indices of insulin resistance derived from OGTT. Both Matsuda index and hepatic insulin resistance were improved after ASTX (12mg/day) supplementation, although muscle insulin sensitivity index was unchanged. Our results suggest that ASTX might have beneficial effects on the prevention of diabetes in subjects whose HbA1c was from 5.6 % to 6.4 %, including subjects with prediabetes. Disclosure M. Urakaze: Research Support; Self; Fuji Chemical Industry Co., Ltd.. C. Kobashi: None. Y. Satou: None. M. Takagi: None. K. Shigeta: None. M. Toshima: Research Support; Self; Fuji Chemical Industry Co., Ltd. J. Takahashi: Employee; Self; Fuji Chemical Industry Co., Ltd. M. Nishida: Other Relationship; Self; Fuji Chemical Industry Co., Ltd..