Health and Tea – Posting #2 in a Series

Posted by Melanie Hingle, MPH, RD (Center for Physical Activity and Nutrition, University of Arizona

As if we needed more proof that tea is good for you!…a new study published in the journal Cancer Epidemiology Biomarkers & Prevention (by Yang et al. Vol 16, Pages 1219-1223) found a 37% risk reduction for colorectal cancer in a population of 69,710 Chinese women between the ages of 40 and 70. The ones who appeared to derive the most protection from tea were those who “regularly” drink tea. Now, what does “regular” mean? This is always a good question to ask when reading about research studies on diet and behavior.
This particular study doesn’t go into the specifics, but suggests that ‘daily’ intake is associated with a greater protective benefit. Green tea is the most commonly consumed tea in Shanghai so this is the tea that the study has the most information on — so the results aren’t necessarily applicable to other types of tea (although I suspect similar benefits).
With this type of population research, the results can only be broadly applied to the specific population being studied (in this case, middle-aged Chinese women)…however, results are convincing enough to suggest a benefit could be derived from tea drinking behaviors in OTHER populations as well if they used similar quality tea, and prepared it in a similar manner. In Shanghai, “the common method of tea preparation is to brew dry leaves with hot water” according to the authors of this study. I am not certain how this differs from our American way of preparing tea (e.g. I too brew with hot water?) – perhaps they mean versus cold water brewing? If someone knows, please do let me know – I suspect Austin knows!:)
Lastly, an effect was also noted for the “dose” of tea – i.e. longer duration of tea drinking (years) corresponded with significantly lower risk.

Happy tea drinking!