Diabetes Helped by Green Tea, New Studies
Diabetes has reached epidemic proportions and can be a challenge to treat. Several new studies show how green tea may help patients better manage this disease and diabetic complications.
Green tea has compounds that help diabetes
Green tea is widely studied for a variety of health issues, and for good reason. Among its many helpful components are potent antioxidants called polyphenols, and a catechin called epigallocatechin gallate (EGCG) is of special interest.
In fact, scientists are so interested in EGCG, there is currently a clinical trial underway that is exploring how the green tea component affects the body’s response to insulin. While that study is underway, others have been completed, and here are some of the findings.
In a new study from Brazil, researchers explored the ability of green tea to protect the retina in diabetic rats. This information is critical because diabetics are prone to developing diabetic retinopathy, an eye condition that can result in blindness.
The researchers administered green tea to rats with diabetes and hypertension for 12 weeks. They discovered how treatment with green tea protected the retina against damage associated with glutamate (an amino acid) toxicity. Based on this finding, they noted they had found “a novel mechanism by which GT [green tea] protects the retina against neurodegeneration in disorders such as diabetic retinopathy.”
In a new study released in the February 2013 issue of Current Opinion in Lipidology, the multinational team of investigators reported on results from studies on plant components called flavonoids and the development of type 2 diabetes and heart disease.
Based on their analysis, they noted that “the strongest evidence exists for a beneficial effect of green tea” on bad cholesterol (low-density lipoprotein, LDL) levels and that “flavan-3-ols from green tea and cocoa may lower the risk of type 2 diabetes and cardiovascular diseases.” They did stress, however, that more trials need to be conducted to confirm these findings.
Finally, in a new study from China, a research team looked at the effect of green tea polyphenols on fat deposits in rats fed a high-fat diet. Since overweight, obesity, and diet are critical factors in type 2 diabetes, patients and experts alike are always interested in ways to better manage these risk factors.
In the study, the rats were fed a high-fat diet and given three different dosages of green tea polyphenols in their drinking water. Over time, the scientists observed that the green tea polyphenols reduced fat deposit and levels of adiponectin (a protein that has an important role in glucose and lipid metabolism), as well as other benefits important for diabetes.
Can drinking green tea and/or taking green tea supplements improve your ability to prevent or manage diabetes and its complications? So far there is a considerable body of evidence suggesting green tea and its potent polyphenols have the potential to help individuals who have diabetes and diabetes risk factors, and these new studies add to the growing literature.
van Dam RM et al. Dietary flavonoids and the development of type 2 diabetes and cardiovascular diseases: review of recent findings. Current Opinions in Lipidology 2013 Feb; 24(1): 25-33
Silva KC et al. Green tea is neuroprotective in diabetic retinopathy. Investigative Ophthalmology and Visual Science 2013 Jan 8
Tian C et al. Green tea polyphenols reduced fat deposits in high fat-fed rats via erk1/2-PPARy-adiponectin pathway. PLoS One 2013; 8(1): e53796