It is widely know that lifestyle factors such as processed sugar intake, obesity and lack of exercise significantly increase the risk of type two diabetes (T2D). The benefits of polyphenol rich foods are much less talked about despite the increasing evidence. Polyphenols are the gifts from nature which give food its colour, taste and aroma as well as having numerous health benefits ranging from reducing arthritis, heart disease and cancer. This blog explores the data that they help protect us from diabetes.
Evidence that polyphenols rich food lower diabetes risk
Various environmental and prospective cohort studies have reported links between a higher intake of polyphenol rich foods such as turmeric, cinnamon; broccoli, tea, coffee, chocolate, pomegranate, red wine and berries are linked to a lower risk of T2D [2,3,4,5]. The most notable studies included The Nurses’ Health Study, which investigated urinary excretion of eight polyphenol metabolites and found that anthocyanins, flavanones and flavonols as well as the phenolic acid, caffeic acid, were associated with a significantly lower T2D risk . This was in accordance with the Health Professionals Follow-Up Study, which found that higher polyphenol intake was significantly associated with a lower risk of T2D . Both the Women’s Health Study and a large Finnish cohort study reported that apple consumption of ≥1 apple/day showed a lower risk compared with no apple consumption [2,5]. In addition to these large cohort studies, a laboratory study demonstrated that glucose transport in gut cells was inhibited by flavonoid glycosides and non-glycosylated polyphenols such as epigallochatechingallate, rich in green tea. A study amoung human volunteers both with and without diabetes reported that polyphenols, especially the large polymeric type or condensed tannins found in leguminous foods significantly reduced the glycemic index of simultaneously consumed carbohydrates .
How do polyphenol rich food help protect us from diabetes?
The underlying mechanisms of how polyphenols have sugar lowering properties include inhibition of α-amylase and α-glucosidase, inhibition of glucose absorption in the intestine by sodium-dependent glucose transporter 1, stimulate insulin secretion and reduce hepatic glucose output. Polyphenols may also enhance insulin-dependent glucose uptake, activate 5′ adenosine monophosphate-activated protein kinase .
How to increase your polyphenol intake?
As well as exercising regularly and reducing processed sugar intake, try to add colour, spice and flavor to every meal. For breakfast, as well as avoiding processed sugar add fruit, berries and nuts. Have salad or leafy green vegetables with every meal and liberally us herbs, garlic, chilli and other spices. The recipies in this blog provide examples of low sugar, high polyphenol rich meals. In addition, consider a polyphenol rich whole food supplement.
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