Most people think of green tea as a healthy beverage and with good reason. People who choose green tea as the drink of choice may be to reduce their risk of heart disease, cancer, dementia, stroke, diabetes, and even lower the risk of obesity. Although more research is needed to confirm these positive effects, see preliminary results encouraging. What about the negative aspects of drinking green tea? A special group of components, tannins in green tea, has received some scrutiny. These astringent polyphenols gives tea a bitter taste when present in large quantities. ? Is tannins in green tea really healthy
What are tannins?
tannins are present not only in green tea leaves, but in a number of other plants and help to protect plants from predators such as animals and insects. They are also present in red wine and give the tart taste that most wine producers want to avoid. They give unripe fruit its characteristic bitter taste, and is even found in beer and chocolate. As unappetizing as it may sound, tannin also used to tan leather.
Is tannins in green tea Beneficial?
The tannins in green tea has anti-inflammatory, antibacterial, antiviral, and antiparasitic effects, and has even been shown to inhibit replication of the HIV virus. It is hardly surprising that the tannins would have these benefits since one of their main functions is to protect plants from predators and disease. One way in which tannins in green tea can be useful for humans is by killing the bacteria that cause gingivitis or gum disease. They may also help in treating diarrhea and can reduce the risk of wound infection.
Do tannins in green tea have negative effects?
One of the biggest problems associated with tannins in green tea is their effect on iron absorption. Tannins forms a complex with iron in the gut making it less easily absorbed and utilized by the body. For this reason, it is recommended that green tea did not drink with meals to avoid interfering with iron absorption. Adding lemon to green tea can offset some of the effect of tannins in iron absorption. The tannins in green tea can also cause nausea and mild digestive upset in sensitive individuals. Tannin slow down protein digestion although large quantities would be needed for this to be a problem.
The Bottom Line?
The tannins in green tea have both positive and negative effects. The main concern is the effect they have on iron absorption. To offset this effect, drink green tea only between meals and add few drops of lemon juice to each cup. This will help increase the absorption of iron and increase the bioavailability of catechins that make green tea so healthy drink. If you have heart disease or high blood pressure, talk to your doctor before drinking caffeinated drinks such as green tea.