Polyphenols Associated With Improved Insulin Sensitivity
Plant-derived foods that are rich in polyphenols have previously been associated with several cardiometabolic health benefits. A new study has found that eating more polyphenol-rich foods may help improve insulin sensitivity in overweight and obese non-diabetic, insulin-resistant people.
Participants in the study included 41 overweight and obese adults, 18 of whom were men and 23 of whom were post-menopausal women.Over the course of six weeks, half of the group was given a drink containing dry strawberry and cranberry polyphenol extracts, for a total of 333 mg of polyphenols. The other half was given a pomegranate-derived red food color and flavor drink to mimic the polyphenol drink. All of the participants were asked to follow their usual food and exercise habits and were forbidden to consume berries, polyphenol supplements, and any products containing berries or wine.
Insulin sensitivity was assessed at the beginning and the end of the study period via a hyperinsulinaemic-euglycaemic clamp. Glucose tolerance and insulin secretion were assessed using a 2-h oral glucose tolerance test.
At the conclusion of the study, the researchers noted an increase in insulin sensitivity in the supplement group when compared with the control. They also noted a lower first-phase insulin secretion response, as measured by C-peptide levels, in the first 30 minutes of the oral glucose test.
There were no notable changes in lipids, markers of inflammation, or oxidative stress in either group.
Researchers from Laval University in Quebec conducted the study. It was published in the February 2017 issue of the British Journal of Nutrition.
Polyphenol intake has been linked with a variety of health benefits, including helping with weight management and reducing inflammation. Polyphenols can be found naturally in many foods, including honey, a variety of fruits and vegetables, red wine, chocolate, tea, certain oils and many types of grain.