Both types of tea are known to have beneficial health effects, one of these healthy aspects of drinking tea is in the combat of cancers. Polyphenol extracts from green tea have been shown to have both a preventative and an ability to fight skin cancers. This section of the time for tea and coffee site takes a look at the link between tea consumption and the risks of developing lung cancers.

Research into Drinking Tea and the Risk of Developing Lung Cancer

Much research has been done on the effects of drinking black and green tea and the development of cancer of the lung. Black tea contains the polyphenol theaflavin, these have been shown to inhibit pulmonary hyper proliferation and tumorigenesis in mice. If mice were given a 0.1% theaflavin solution to drink the rate that the cancer could multiply was reduced by 23% and the volume of the lung cancer reduced by 34%.

One of the reasons that black tea is thought to act as a preventative against cancers is that it is able to reduce the ability of cells to proliferate. Additionally black tea has been shown to induce the death of lung cancer cells.

Other experiments have shown that infusions of black or green teas drank by mice for a 60 week period resulted in a reduction of the cases of lung cancer by over 50%, and the volume of the cancers that did develop by 10 fold.

Caffeine and Lung Cancer

Interesting it is not only the theaflavins found in tea that have a positive effect upon the risk of developing cancers. Research has shown that caffeine was able to reduce total lung tumours by five fold in rats (theaflavins reduced lung cancer by about 50%). It is thought that one of the main components that acts to combat lung cancer in tea is therefore caffeine. However black tea does contain a small amount of antioxidant catechins and these have also been demonstrated to combat cancers. It is therefore thought that many of the compounds that are found in black tea are likely to have an anti-carcinogenic effect.

Human Tea Consumption and Lung Cancer

Studies in China that have looked into the link between green tea consumption and lung cancer in humans found that in people who did not smoke the greater the amount of tea that was drank the lower the incidence rate of developing lung cancers. Another study carried out that looked at smokers in Uruguay found a positive correlation with green tea consumption and a lowering of the risk of lung cancer.

Although much work still needs to be carried out into the relationship of drinking tea and the lowering of the risk of developing lung cancer, it appears that there is both a mechanism for its positive action and a relationship between drinking tea and reducing the risks of cancer development.

References

Khan and Mukhtar (2007) Tea polyphenols for health promotion. Life Sciences 81: 519 to 533.
Landau et al. (1998). Inhibition of spontaneous formation of lung tumors and rhabdomyosarcomas in A/J mice by black and green tea. Carcinogenesis 19: 501–507.
Xu et al. (1992). Inhibition of tobacco specific nitrosamine-induced lung tumorigenesis in A/J mice by green tea and its major polyphenol as antioxidants. Cancer Research 52: 3875 to 3879.
Zhong et al. (2001). A population based case control study of lung cancer and green tea consumption among women living in Shanghai. Epidemiology 12: 695–700.