Consumption of cranberry and blueberry may be associated with an improvement in glycaemic control among patients with type 2 diabetes mellitus (T2DM). The findings were reported by a meta-analysis published in the journal Critical Reviews in Food Science and Nutrition.
Researchers conducted a meta-analysis of 7 randomised controlled trials (RCTs; n=270) identified through a literature search on the LILACS, PubMed/MEDLINE, Scopus, Cochrane Library and Web of Science databases.
Consumption of blueberry extract or powder supplements, corresponding to 9.1-9.8 mg of anthocyanins, for 8-12 weeks was found to have a beneficial effect on glucose control. Similarly, intake of 240 mL of cranberry juice every day for 12 weeks was found to lower fasting glucose concentrations.
Berries are a rich source of polyphenols, especially flavonoids, which are known to influence blood glucose and lipid metabolism. Blueberries have twice the amount of polyphenols than cranberries.
"Our findings suggest a promising use of these berries in the management of T2DM; however, additional studies would be required to better understand the underlying mechanisms," the authors concluded.
