August 22, 2022
1 min read
The study was funded by USDA-NIFA, USDA-HATCH and the Ohio Agricultural Research and Development Center at The Ohio State University. The authors report no relevant financial disclosures.
Green tea extract improved gut health by decreasing inflammation and small intestine permeability in both healthy individuals and those at risk for cardiometabolic disease, according to research in Current Developments in Nutrition.
“There is much evidence that greater consumption of green tea is associated with good levels of cholesterol, glucose and triglycerides, but no studies have linked its benefits at the gut to those health factors,” senior study author Richard Bruno, MS, PhD, professor of human nutrition and director of the Bionutrition Core Laboratory at The Ohio State University, said in a related university press release.
To determine whether the anti-inflammatory properties of catechin-rich green tea extract could reduce gut permeability and inflammation in people with metabolic syndrome, Bruno and colleagues conducted a randomized, double-blind, placebo-controlled crossover study.
They included 40 participants — 21 adults with metabolic syndrome and 19 healthy adults — who received placebo or green tea extract confections (890 mg/d catechins) during two, 4-week interventions, with 1 month off supplements between treatments. The daily dose of gummies was equivalent to five cups of green tea, according to the release.
During the study, participants followed a diet low in polyphenols and provided fecal samples at week 4 for ELISA-based measures of inflammatory proteins. Researchers also collected 24-hour urine samples for analysis of nondigestible sugars.
According to the results, urinary lactulose and mannitol were lower with the green tea extract treatment compared with placebo (P = 0.043) in both metabolic syndrome and healthy participants, as was fecal myeloperoxidase and calprotectin (P = 0.03-0.05).
“We did not attempt to cure metabolic syndrome with a 1-month study,” Bruno said. “But based on what we know about the causal factors behind metabolic syndrome, there is potential for green tea to be acting at least in part at the gut level to alleviate the risk for either developing it or reversing it if you already have metabolic syndrome.”