Tea fights diabetes

September 22, 2009


I grew up in a family where several members drank black tea, meaning without milk, but really it just applies to the type of tea. Black tea, long known for its antioxidants, immune boosting and antihypertensive properties, could also help treat diabetes.

Researchers studied the polysaccharide levels of green, oolong and black teas because polysaccharides are a type of carbohydrate that includes starch and cellulose which help retard absorption of glucose.

The researchers found that of the three teas, the polysaccharides in black tea had the most glucose-inhibiting properties and their polysaccharides also showed the highest scavenging effect on free radicals, which are involved in the onset of diseases such as cancer and rheumatoid arthritis.

In another recent study, participants who drank black tea had significantly reduced plasma glucose concentrations after two hours, compared to those who drank water or caffeine drinks. Drinking black tea also increased insulin levels, compared with the other drinks.

That study linked black tea’s diabetic benefits to polyphenols (naturally occurring antioxidants) and these compounds are thought to work by stimulating your B-cells — pancreatic cells responsible for insulin production — to produce insulin in your body. A growing body of research also suggests that the polyphenols in tea can lower your cholesterol, triglyceride levels and blood pressure, and even help to protect your bones. That study linked black tea’s diabetic benefits to polyphenols (naturally occurring antioxidants), including Epigallocatechin gallate (EGCG), of which more below!

My Green Tea Comment:

Although black tea was found to contain more glucose inhibiting polysaccharides, green tea may still be the most beneficial tea of them all, including for diabetics. A previous study found that EGCG in green tea worked as well in moderately diabetic mice as the diabetes drug Avandia, for example.

Another study in the European Journal of Clinical Nutrition concluded that green tea-extract also had a positive impact on glucose abnormalities. In that study, daily supplementary intake of green tea-extract lowered the hemoglobin A1c level in individuals with borderline diabetes.

So for my money black tea is not as healthy as green tea as they undergo far more processing. Oxidation is the main deciding factor whether you have green, oolong, or black tea, and black tea undergoes the most amount of oxidation through application of high heat. Good green tea is not oxidized at all and, like the Irish fields, the greener it is the higher the quality.

Fluoride is a common contaminant in many black teas and this toxic substance can have profoundly negative effects on your body. Green tea is the least processed kind of tea, and therefore typically contains the least amount of fluoride and the most EGCG of all tea varieties, which is a very good thing for your health.

I am currently trying a new type of green tea, Matcha, which contains the entire ground tea leaf, and can contain over 100 times the EGCG provided from regular brewed green tea. I will let you know how I get on with it.


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One Response to “Tea fights diabetes”

  1. Tonya Thomas on October 20th, 2009 6:58 pm

    Tea seems to have a number of beneficial properties, and more are being discovered all the time. And it’s tasty!

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