Reviewing the Evidence: Is There a Role for Green Teas in Cancer Prevention?
- Author(s): Sun, Yee-Li
- et al.
Consumption of tea has been associated with health amongst Asian populations for centuries. Epidemiological studies performed in the last two decades have proposed that green teas may be able to exert anti-carcinogenic effects. It is now believed that green tea polyphenols (GTPs) like epigallocatechin-3-gallate (EGCG), with their anti-oxidant properties, are the primary mediators of such an effect. Recent studies performed on cultured cell lines, animal models and some human populations have shown promise in elucidating if and how green tea may be of benefit to us. This paper attempts to consolidate some of the current research in the field and provide an overview of the direction that the research is taking with the ultimate goal of trying to answer the question of whether or not we, as health care consumers, should "buy into the hype". Unfortunately, it appears that at present the data remains inconclusive. Despite the results of a large number of benchtop experiments and the existence of epidemiological studies indicating correlation, the fact remains that direct clinical evidence is still lacking. Until more clinical trials are conducted, it will remain difficult to prove definitively the existence of a causal relationship between green tea consumption and reduced cancer risk.