Green tea is brewing up a lot of hope these days, and miraculously, it's serious science types who are most enthusiastic.
This cup-and-saucer remedy is full of antioxidants and is being studied as a cancer preventer or cure, an Alzheimer's treatment and weight loss agent. It's a wonder the Japanese and the Chinese die of anything at all.
There's still much to explore, and studies are being conducted as we speak. I'm not talking about the bogus, sketchy kind either. Keep in mind that when people throw around the word "study," they're often relying on seriously questionable data. But in this happy case, everyone seems to be on the same page.
There's something about green tea. So drink up.
What the experts say
"We were [doing a study] to protect cells with a whole range of flavonoids as well as various polyphenolics [both found in green tea]. We injected the pure phenolic component of green tea, EGCG, directly into the livers of mice. We raised the level until we hit the toxic dose. I had an e-mail from a person with bladder cancer who was taking a gram of ECGC daily (approximately the amount in 300 cups of tea), which is definitely the sort of dose that would concern me. But this guy had bladder cancer, so I wasn't prepared to say he should stop, because it could help. I know green tea will kill cancer cells, but I'm not keen on people taking high doses of these things without proper testing."
PETER O'BRIEN , professor emeritus, Leslie Dan Faculty of Pharmacy, University of Toronto
"I have white and green tea capsules that I recommend for my patients. Tea is a good way to treat not just the gums but the entire body. You can also open the capsules, place the contents on a toothbrush and massage the powder into the gums . White tea is even more effective and more potent as an antibacterial therapy [than green]. The main microbial infestations of the mouth are staphylococcus and streptococcus. For the longest time, the remedy for an infection of the mouth or bleeding from the mouth was to bite on a tea bag."
LEON TREGER , holistic dentist, Toronto
"There may be a hundred or more studies on green tea's anti-cancer effects. We found in test tubes that it blocks production of beta-amyloid, a protein implicated in Alzheimer's. We tested it in animals, and when we treated them with the EGCG compound [a chemical component of green tea], we saw a reduction of plaques and beta-amyloid protein. The real question is whether we can give these doses of EGCG safely to humans. Our research suggests that EGCG has a specific effect, but there are other flavonoids in the tea that oppose this effect, so drinking the tea may not as be effective [as taking EGCG alone]. EGCG is sold on the market as a weight-loss aid. But, again, these are high doses."
DOUG SHYTLE , assistant professor, psychiatry and behavioural medicine, University of South Florida, Tampa
"Green tea's major benefit is its antioxidant content, and that allows it to be used in our field for cancer prevention and detoxification. It's used for asthma, eczema and periodontal disease. Some say it helps with weight loss, but that's only due to its caffeine content. I think just drinking the tea is a great way to get the benefits as long as you use a high-quality product that has high bioflavonoid content."
ANTHONY YORS , naturopath, Toronto
"We are doing a five-year study in relation to cancer prevention. There are lots of studies that suggest green tea may be beneficial in preventing lung and other cancers, like bowel cancer. But most of these are comparative or epidemiological studies and not double-blind randomized placebo-control studies. This is the first of its kind. Many of the [other] studies were done on animals or cell cultures, and the amount of tea used may not be achievable in humans. It seems it has anti-inflammatory properties and can lower cholesterol and blood pressure, but we need to confirm this. Taking huge doses is not advisable . It can cause vomiting, gastritis, even ulcers, and there are changes in the blood as well, so I want people to be careful."
STEPHEN LAM , professor of medicine, University of British Columbia, chair of the lung cancer group, BC Cancer Research Centre, Vancouver