- Anti-inflammatory properties in green tea may benefit gut health and blood sugar, according to researchers.
- The results are particularly promising for people with metabolic syndrome, which is a cluster of conditions that includes high blood sugar and excess belly fat.
- One of the coauthors of the study told Insider that future studies should look at what amount of green tea provides the most benefit, with the least side effects.
Drinking green tea may lower blood sugar levels and promote better gut health, according to a study published June 14 in Current Developments in Nutrition.
Researchers from Ohio State University conducted a small study of 40 participants who ate green tea extract gummies containing the equivalent of 5 cups of green tea a day for 28 days. 19 of the participants were healthy individuals, while the other 21 had metabolic syndrome, which is a cluster of conditions which includes high blood pressure, high blood sugar, excess belly fat, and abnormal cholesterol levels, according to the Mayo Clinic. Metabolic syndrome affects more than a third of Americans, according to Healthline, and puts patients at greater risk for type 2 diabetes, heart disease, and stroke.
Participants randomly received the green tea extract or placebo for a 28-day period, but weren't told which one they got. After a month break between, the other group received the opposite substance. Participants were told to eat foods low in antioxidants called polyphenols during the green tea and placebo period, to control for any benefits that could come from other foods instead of the extract itself. Fecal and urine samples were used to measure inflammation and blood sugar levels.
Researchers found that green tea extract reduced blood sugar levels, gut inflammation, and gut permeation in participants with and without metabolic syndrome. Gut permeability is the intestines' ability to absorb water and nutrients from food, according to the Cleveland Clinic. Higher gut permeability is associated with leaky gut syndrome, which is not a recognized medical diagnosis, but is a theory that says in some cases, intestines are too absorbent, which allows toxins into the bloodstream that may create an inflammatory response.
The study suggests that green tea's anti-inflammatory chemicals called catechins can help improve gut health, as well as the body's ability to control glucose levels. The results are particularly promising for people with metabolic syndrome, since inflammation and high blood glucose levels are thought to be contributing factors, according to the National Heart, Lung, and Blood Institute.
Coauthor of the study, Dr. Joanna Hodges, told Insider that future studies should look at what amount of green tea extract provides the most benefit without adverse effects. She also said that more research should be done on how green tea extract can benefit other intestinal conditions, such as irritable bowel disease.