Scientists from Linus Pauling Institute, Oregon and USANA Health Sciences, Inc., Salt Lake City have demonstrated that tea and grape seed extracts can lower the conversion of starch into glucose in the body. This is good news for suffers of type II diabetes who are often prescribed enzyme inhibitors which, although very effective at reducing blood glucose levels can also cause side effects such as diarrhea and stomach cramps.
The team evaluated green tea, white tea and grape seed extracts as inhibitors of α-amylase and α-glucosidase and compared them to the pharmacological inhibitor, acarbose. Grape seed extract was better than acarbose at inhibiting both enzymes, green and white tea were not so effective at lowering α-amylase activity but were good at lowering α-glucosidase activity.
The paper is published ahead of print on the Journal of Agricultural and Food Chemistry website.