Researchers studied the polysaccharide levels of green, oolong and black teas and whether they could be used to treat diabetes.
Polysaccharides, a type of carbohydrate that includes starch and cellulose, may benefit people with diabetes because they help retard absorption of glucose.
The researchers found that of the three teas, the polysaccharides in black tea had the most glucose-inhibiting properties. The black tea polysaccharides also showed the highest scavenging effect on free radicals, which are involved in the onset of diseases such as cancer and rheumatoid arthritis.
While this study was done with black tea, which is the most common form of tea consumed in the US, it is not as healthy as green teas, which essentially have the same benefits but are less damaged as they go through less processing.
All teas, black, green and oolong, are all derived from the Camellia sinensis evergreen plant. The difference between the teas comes from the amount of oxidation and type of processing each tea goes through.
Oxidation is the main deciding factor whether you have green, oolong, or black tea, as the oxidation process causes the leaves to turn bright copper or black in color.
Whereas black tea undergoes the most amount of oxidation through application of high heat, high quality green tea is not oxidized at all. This is how you can tell the quality of your green tea; the greener, the higher the quality as it signifies the least amount of oxidation.
While the rest of my comment addresses the study, please realize that my strong recommendation would be to consider green or herbal teas instead, which I believe are superior.
How Tea Benefits Diabetics
This is not the first time researchers have found tea to be beneficial, especially for diabetics. And although I still believe water should be your beverage of choice and make up the majority of your fluid intake, adding tea to your day is a sensible choice with many health benefits.
This latest study concentrated on a natural polysaccharide compound that mimics type 2 diabetes drugs Precose and Glyset. Compared to green and oolong tea, black tea was found to contain the most of this particular substance.
The tea polysaccharides reduce your blood sugar by inhibiting alpha-glucosidase, an enzyme that turns starch into glucose. The two drugs mentioned above work by inhibiting this enzyme as well.
But it’s quite likely that there’s more than one master ingredient that gives black tea its power to be of help against diabetes.
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), including:
- Epigallocatechin gallate (EGCG)
- Epicatechin gallate
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.
Epigallo-catechin gallate (EGCG), specifically, has shown potential to fight a number of diseases aside from diabetes, including:
Specific health benefits of EGCG include:
Quality and Purity May Be More Important Than the Type of Tea You Drink
Fluoride is not what most people think about when they think about tea, but it is a common contaminant in many teas.
Fluoride is a toxic substance that can have profoundly negative effects on your body. So, when I make the recommendation to drink tea, it’s with the caveat that the tea be of high quality and free of fluoride.
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. Aside from water, I believe high-quality green tea is one of the most beneficial beverages you can consume.
I prefer matcha green tea because it contains the entire ground tea leaf, and can contain over 100 times the EGCG provided from regular brewed green tea.
In addition, I also recommend drinking your tea “straight,” avoid adding sugar, artificial sweeteners, milk or other unhealthy additions.
Green Tea May Be the Healthiest Choice of All
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.
One previous study found that EGCG in green tea worked as well in moderately diabetic mice as GlaxoSmithKline’s 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.
How is Matcha Green Tea Different From Other Green Teas?
Many green teas have been oxidized, and this process may take away many of its valuable properties. The easiest sign to look for when evaluating a green tea’s quality is its color: if your green tea is brown rather than green, it’s likely been oxidized.
The matcha tea is a vibrant bright green, and is far less processed and of much higher quality than most other green teas, so you also avoid the risk of ingesting high levels of fluoride, lead, and aluminum, which can be found in inferior teas of all kinds, including green teas.
Rather than being steeped and strained like typical tea, matcha tea is made of tea leaves ground into a powder, and you add the powder right into the water. Since you are consuming the whole leaf in this way, matcha tea is said to be one of the healthiest green teas out there.
Preventing and Treating Diabetes
Clearly, if you have diabetes then medication is not the answer you’re looking for.
Doctors usually talk about diabetes as a disease of blood sugar. However, type 2 diabetes is more correctly a disease of insulin and leptin signaling -- both of which can be corrected through proper diet and exercise.
So before resorting to drugs for diabetes, I suggest learning about how food and exercise can be your allies to better health, and adding a few cups of green tea to your day could be one beneficial addition.
My book, Take Control of Your Health, will arm you with everything you need to know to start eating right for your body and taking care of yourself physically and emotionally. I’ve also compiled a comprehensive, free online guide that will educate you on how to make type 2 diabetes finally disappear.