Special Edition: Blood Sugar Management
Polyphenols
A review published in the Journal of Nutritional Science (Coe et al. 2016; 5: e24): “This systematic review shows that there is potential for the postprandial [glycaemic response] and resulting [insulin response] to a food or meal to be reduced, especially the peak response, with the addition of polyphenol-rich sources at doses easily obtained in the diet.
“Consuming polyphenol-rich sources in the form of beverages, foods or extracts may therefore be a strategy in diabetes management and obesity prevention.”
Similar conclusions were reached by scientists in a review published in Nutrients (Kim et al. 2016, 8(1), 17), which noted several potential mechanisms of action: “Dietary polyphenols may inhibit alpha-amylase and alpha-glucosidase, inhibit glucose absorption in the intestine by sodium-dependent glucose transporter 1 (SGLT1), stimulate insulin secretion and reduce hepatic glucose output.
“Polyphenols may also enhance insulin-dependent glucose uptake, activate 5′ adenosine monophosphate-activated protein kinase (AMPK), modify the microbiome and have anti-inflammatory effects.
“However, human epidemiological and intervention studies have shown inconsistent results. Further intervention studies are essential to clarify the conflicting findings and confirm or refute the anti-diabetic effects of dietary polyphenols.”
Clinical trials are indeed under way, with a parallel, double-blind, placebo-controlled and randomized clinical trial of 41 overweight and insulin-resistant subjects recently completed by scientists at the Institute of Nutrition and Functional Foods at Laval University, Canada in collaboration with Atrium Innovations.
The data, which is still to be published, supports a combination of strawberry and cranberry polyphenols to improve insulin sensitivity in overweight and non-diabetic, insulin-resistant adults.
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