Time for coffee and tea
Black tea and the prevention of cancer
Tea is a beloved drink of the British, with around 75% of the population being daily consumers of the beverage. On average they drink about 3 cups (a pint) per day. This has many health implications as black tea contains both beneficial components such as antioxidants in the form of flavonoids and minerals, and possibly harmful components (if consumed in great quantities) such as caffeine.
Gardner and colleagues have done a round up of research done looking at the implications of the consumption of black teas and many health topics such as heart disease, risk of cancer and impact upon bone strength.
Much work has been done on green tea that has shown that the antioxidants in them (catechins) can reduce the risk of getting many cancers. Recently there has been a interest in the impact of black tea antioxidants on health, after all over 80% of the tea consumed in the world today is in the fermented black form. In addition to its antioxidant properties flavonoids have other health aspects such anti-inflammatory and anti-tumor forming capabilities.
Gardner and colleagues found 26 papers that related the consumption of black tea and cancers. Most of the papers looked at the relationship of black tea consumption and colorectal cancer. It was hard to conclude from the research whether black tea was able to reduce colorectal cancer due to other lifestyle impacts such as diet, smoking, drinking, social status etc. However some research strongly suggests that drinking one and a half (half a pint) of black tea per day can have a positive impact on reducing the risk of colorectal cancers.
Of the 26 studies only two found a negative relationship between drinking black tea and colorectal cancer, and these studies were done on people who had fatty diets, which is more than likely the reason for an increased incidence of colorectal cancer has opposed to the consumption of black tea. Additionally there has been a paper by Mendilaharsu and colleagues that has shown a positive effect of drinking tea and a reduction of the risk of getting lung cancer.
It is thought that drinking tea will not have any ill effects with regard to the risk of cancer, and that more research specific research should be carried out to look at any possible positive effects of the consumption of the beverage and the risk of colorectal and lung cancers.
Black tea and health part four: Dental bone healthReferences