Green Tea or Black for Preventing Breast Cancer?

In recent years there has been an abundance of research investigating the benefits of green and black tea on preventing disease. And, the results have been divided. Depending on the health condition being evaluated, some studies have shown green tea to be more effective, while others have shown green and black tea to be equally effective.
Green tea differs from black in its processing. Both come from the Camellia sinensis plant, but black tea is fermented when processed. This fermentation changes some of the tea plant’s compounds, and effectively reduces some of the most important anti-oxidants, namely EGCG, one of the most important anti-oxidants you can consume. However, black tea does still contain many other important anti-oxidants.
When it comes to preventing many forms of disease, EGCG seems to be an important component, making green tea the drink of choice. In addition, the reason tea came into focus in the first place was the noticeably lower rates of disease in Asian countries, where tea is consumed in large quantities - most of it green tea.
One of the diseases that tea is reported to prevent is breast cancer. Several studies have shown that tea, green in particular, seems to significantly lower your chances of developing breast cancer. Some studies have even suggested that green tea could even be an effective treatment for breast cancer.
One study conducted on breast cancer patients undergoing chemotherapy noted that those participants who regularly consumed green tea during their chemotherapy treatments showed higher concentrations of the chemotherapy drugs in their cancer cells than those who did not consume green tea.
Other studies have indicated that green tea can inhibit the growth of cancer cells, possibly preventing the spread of the disease. And, additional studies have shown that green tea may prevent the recurrence of breast cancer in patients diagnosed at Stage I or II of the disease.
But, what about black tea? Why have similar results not been shown with the consumption of green tea? The theory is that it has to do with hormones.
Green tea is thought to reduce certain circulating sex-steroid hormones, such as estone and estradiol, and that black tea may increase the levels of these hormones. If the reduction in breast cancer risk is due to the lower level of these sex-steroid hormones, then it’s easy to see why green tea is more effective at preventing breast cancer than black tea.
One study in Singapore evaluated a cross section of 130 healthy post-menopausal Chinese women. Their tea consumption broke down like this:
• 84 were non or irregular tea drinkers – meaning they drank tea less than once a week.
• 27 were regular green tea drinkers – meaning they drank green tea weekly or daily
• 19 were regular black tea drinkers
The study concluded that, relative to the estrone levels in the non tea drinkers, the green tea drinkers showed a lower estrone level, and the black tea drinkers showed a higher estrone level. In fact, the green tea drinkers showed a 13% lower estrone level, and the black tea drinkers showed a 19% higher level of estrone than those who did not drink tea. A similar relationship was found between tea drinking habits and estradiol levels.
While this study alone cannot be considered conclusive, it does suggest that, if high levels of circulating sex steroids increase the risk of breast cancer, green tea is a much better preventative than black tea.
Most researchers agree that having high levels of circulating hormones like estrogen (which is made up of estradiol and estrone) after menopause does increase your risk of breast cancer. This is why women who take hormone supplements to help ease the symptoms of menopause have an increased risk of developing cancer over women who do not treat their menopausal symptoms with hormones like estrogen therapy.
So, if you’ve experienced menopause and you’re at an increased risk for breast cancer, talk to your doctor about tea drinking. Particularly if you drink large quantities of black tea, it might be wise to reduce this amount, and replace it with green tea.
It’s clear that we don’t fully understand the relationship between tea and breast cancer, and that much more research should be performed. However, we do have a pretty clear picture that green tea prevents many forms of cancer, breast cancer among them.
So, it’s probably a good idea to keep drinking your green tea. While it’s true that we don’t have all the answers, it does seem clear that green tea offers many health benefits and that drinking it is a healthy habit that all of us should get into.
Green tea is delicious, refreshing and widely available. All of these attributes make green tea a simple way to improve our health and reduce the risk of certain diseases. So, make a cup of green tea, and drink to your health!