What's great about green tea?
Wednesday, February 6, 2019
Q: What’s so great about drinking green tea? If you convince me to try it, what should I look for? There are so many products and so many claims. AD, Greenville
A: I have fond memories of my first visit to a tea field in Kenya — a beautiful sight. Green tea is one of those drinks that wears a halo — everyone thinks it is healthy and it can have some health promoting actions. I have tried it in all its forms — brewable, matchas or powdered, bottled and in supplements since there is evidence that green tea is good for heart health, cancer prevention, weight management, and memory.
But, I never developed a liking for black, green, white, oolong or the local favorite -- sweet tea. So, Sarah Keever, an ECU dietetic student will answer your questions. Here is what she wants you to know.
Next to water, tea is the most widely consumed beverage and there is no other beverage like it. Green, black, white and oolong teas all come from the same camellia sinesis plant. How it is harvested and processed makes the difference in color, flavor, and content.
Green tea has more polyphenols and therefore is thought to have more health promoting qualities. People report that drinking green tea has calming effect — perhaps from its health benefits or maybe the warm sensation it gives. The polyphenols in tea help with reducing inflammation and can work to lower high blood pressure and cholesterol, reducing your risk for developing heart disease.
Now, there are claims, too, that drinking green tea can prevent cancer, but it is the antioxidant properties that reduce the formation of free radicals or the molecules that cause destruction to cells. The polyphenol of interest is ECGC, short for Epigallocatechin gallate,which also comes in a dietary supplements.
Type 2 diabetes is a fast-growing condition in the United States and there is great interest in the polyphenols in green tea having an almost “antidiabetic effect.” There is evidence that green tea mimics the effects of insulin in the body and prevents the liver from producing glucose which in turn may help regulate blood sugar levels and perhaps help with weight loss.
Tea has caffeine too. Green and oolong tea have about 30 to 35 mg of caffeine per cup and black has 50 to 90 mg of caffeine per cup. While some people are sensitive to caffeine and experience side effects like jitters, others may experience improved mood and brain function and improved exercise performance. The experts think it takes about 3 cups of green tea to obtain health benefits and that keeps the caffeine below the 200 mg level that causes some people concern.
You are right that there are all types of products on the market and finding the taste you like is important if you are going to consistently drink tea for its health benefits. For the fewest calories, the ingredient list on the back of tea bag should be simple and read just green tea. A few brands have a variety of flavors added like coconut, ginger or orange peel that may or may not add calories. Check the label.
Teas that are ready-made and come in a carton or jug have many other additives such as high fructose corn syrup and food coloring. For example, one Green Tea Citrus product has 100 calories per serving because of the sugar additives. You may be better off brewing your tea or buying an unsweetened product and add a teaspoon of honey for sweetness with only 20 calories. A safe way to check for any sneaky ingredients is to read the back of the container. If you can’t identify the ingredient, perhaps you should find a different brand. Most flavored teas are fruit flavored -- peach, blueberry and even pomegranate and will have the natural flavor, the peel or have other fruits in it.
If you are not sure if you will enjoy the delicate flavor of green tea, buy a variety pack and try them all. Green tea is not a cure-all for disease. Most of the research has been done comparing populations of people who drink tea versus those who don’t. There have been few clinical trials in humans to prove the benefits. Having said that, drinking green tea every day rather than an apple a day, may keep the doctor away.
Professor emeritus Kathy Kolasa, a registered dietitian nutritionist and Ph.D., is an affiliate professor in the Brody School of Medicine at ECU. Contact her at firstname.lastname@example.org.