A very interesting study evaluated the effect of green tea extract on hemoglobin A1c, an important indicator of long term blood sugar control (approximately 3 months).
The study involved 60 subjects with mildly elevated hemoglobin A1c. That result averaged 6.2% which would correlate with a daily blood sugar of 128.
After two months of taking the green tea, the hemoglobin A1c dropped to an average of 5.9% which correlates to an average daily blood sugar of 119. In addition to the improvements in blood sugar, the subjects who took the green tea extract also enjoyed a slight but significant decrease in diastolic blood pressure.
Green tea has proven over and over again to be a valuable tool in the fight against many diseases including cancer, heart disease and diabetes. This study just adds to the already impressive track record for this valuable and inexpensive supplement.
Although the results of this study were impressive, I feel that if they had continued treatment for three months rather than two, we may have seen even better blood sugar control.
In this study, the subjects received a green tea supplement that was standardized to contain 544 mg of polyphenols. These are a class of plant compound that has antioxidant and anti-cancer qualities. I personally use a product called Mega Green Tea by Life Extension Foundation, which contains a spectrum of powerful green tea antioxidant compounds, one capsule once or twice a day should more than meet the green tea polyphenol needs of the body.
(Source: Eur J Clin Cutr. 2008 Aug;62(8):953-60)