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Tea It Up
I received a question recently from a Diet Dish reader asking about green tea. Do you need to buy specialty tea or is grocery store tea in the bag just fine? What kind of nutrients does it have and how much do you need per day?
Let me start out by saying that green tea gets a lot of press for being good for you, but black tea is also very good! Both green tea and black tea are full of flavonoids, a type of antioxidant of antioxidant that helps protect your cells from free radical damage. Tea is considered by many health organizations to be a functional food, meaning it has health properties beyond just the basic vitamins and minerals. Green and black tea both contain about 150-200 mg of flavonoids per brewed cup.
Tea is a great beverage because it is very low in calories at less than 2 calories per cup. It is fairly low in caffeine, depending on how strongly it is brewed, too. The caffeine content of a cup of hot tea is between 15 and 60 mg and iced tea is between 10 and 50 mg per 12 ounces.
Green tea gets extra attention because of the EGCG (epigallocatechin gallate) which is a polyphenol compound that is a powerful antioxidant. Green tea has more of this compound than other teas because of how it is processed. Black and oolong tea are made from fermented leaves, unlike green tea which is steamed, preserving that EGCG.
You may have heard that EGCG speeds up metabolism and can aid in weight loss. While it may slightly increase metabolism, I don’t think the research is strong enough to cause weight loss in people adding a mug or two a day.
Potential health benefits
Tea has been linked to decreased risk of certain cancers and heart disease as well as potentially enhancing the immune system. However, eating a healthy diet, maintaining healthy weight, and exercising regularly has been proven to be much more effective at preventing disease.
Green tea supplements in pill form are not the same thing as brewing and drinking tea. The research is done on the actual tea, not the supplements.
Also, If you are on the drug Coumadin, do not drink a lot of green tea. It does contain some Vitamin K which can interfere with blood thinning drugs such as Coumadin.
Most of the studies done on the potential health benefits of tea used fairly large amounts of tea—more than 5 cups daily. While drinking this much tea is common in Asia, Americans do not generally drink as much. Researchers do recommend that drinking at least 2 cups per day for the potential benefits. I have found a lot of research done by Lipton, so I think "grocery store" green tea is just fine--no need to get loose tea or to spend a lot of money on tea.
You can get a large amount of flavonoids from all kinds of tea. If you enjoy it, drink it. Don’t expect it to absolutely prevent cancer and heart disease, but the more foods (and beverages) you include in your diet that do contain antioxidants the better! Go brew yourself a mug and enjoy.
Photo courtesy of Chaparral [Kendra]