How many of you are tea drinkers? If you’re a tea aficionado, you’re probably feeling pretty smug about all the positive news that’s come out over the past few years regarding the health benefits of tea. Tea has often been maligned because of its caffeine content, but now we know that tea is a powerhouse of antioxidants that may prevent all sorts of health problems. This week, I’ll focus on green tea in particular.
Now that summer is upon us, many of you probably reach for a glass or bottle of iced tea to quench your thirst. New to the market are bottles of iced green tea (remember the days when iced tea only came in a powder that was more sugar than tea?). Several companies now make iced green tea, including Lipton, Snapple and AriZona.
What’s so great about green tea, anyway? Well, first, green tea comes from the same plant as black tea, Camellia sinensis. While green tea might be something more of a novelty in the United States, it’s actually been quite popular in China for, oh, the past 5,000 years or so. Green tea is made from the unfermented leaves of the tea plant, and supposedly contains the highest amounts of polyphenols, which are types of antioxidants that fight free radicals and possibly prevent certain types of diseases.
For thousands of years, people in China, India, and Thailand have used green tea for numerous medicinal purposes. Thanks to population studies, we now know much more about the health properties that green tea has to offer. For example, green tea may help prevent heart disease by improving cholesterol levels. In one recent study, 90% of the subjects who drank one liter of green tea daily for four weeks had a 9% reduction in LDL (bad) cholesterol, and, in 69% of the subjects, there was a 4% increase in HDL (good) cholesterol.
In another study, done with rats with diabetes, green tea helped lower blood glucose levels and also prevented the formation of diabetic cataracts. To get the same benefits, humans would need to drink about five 8-ounce cups of green tea every day.
Green tea may also help people with insulin resistance, a precursor to diabetes. In another study, also done with rats, green tea helped lower fasting glucose, fasting insulin, and fasting triglyceride levels. And the rats also had a decrease in the amount of visceral fat (the kind of fat that can contribute a host of health problems, including diabetes).
Other studies point to possible benefits of green tea in preventing different types of cancers, including breast, ovarian, bladder, lung, and pancreatic cancers. Some inconclusive evidence also points to a role for green tea in weight loss. Several studies have shown that drinking green tea or taking green tea as a supplement can speed up metabolism (the rate at which you burn calories). This effect is apparently due to a compound in tea called epigallocatechin gallate (EGCG)—try dropping this term at your next cookout!
Obviously, more research needs to be, and likely will be, done looking at the effects of green tea on health. In the meantime, if you’ve never tried green tea, give it a go. Hot or cold, green tea has a fairly mild flavor. If you prefer cold green tea for the hot summer months, a few words of caution are in order: Many of the “ready to drink” bottles of iced green tea can are loaded with calories and carbohydrate.
For example, a 20-ounce bottle of AriZona Green Tea with Ginseng & Honey contains 175 calories and 45 grams of carbohydrate (that’s like eating three slices of bread). Fortunately, AriZona makes a diet version with practically no calories and only about 2 grams of carbohydrate. The same pretty much holds true for Lipton’s Green Iced Tea with Citrus—a 16.9-ounce bottle has 169 calories and 44 grams of carb, but the diet version contains no calories or carbs. Lipton also makes single-serving packets of iced green tea powder called “Green Tea To Go” that you add to water, and these, too, have no calories or carbs. Snapple also has a diet green tea. As always, read the label of any food or beverage for serving size and total carbohydrate. Cheers!