The research study "Tea Consumption and the Risk of Overall and Grade Specific Prostate Cancer: A Large Prospective Cohort Study of Scottish Men" is published in the Nutrition and Cancer Journal
. It was led by Dr Kashif Shafique of Glasgow University's Institute of Health and Wellbeing and based on a sample of 6016 men.
The study references black tea, rather than green tea, but tea drinking habits were not monitored to the extent that participants were asked if they added milk or sugar to their tea.
reported the study found "6.4 per cent of those who consumed at least seven cups of tea per day contracted prostate cancer compared to 4.6 per cent of those who drank three cups at most." Taking into account the age, lifestyle and health of the participants, researchers concluded heavy tea drinkers were 50 percent more likely to develop prostate cancer. However researchers stressed "Further research is needed to determine the underlying biological mechanisms for the association."
Dr. Shafique said
“I was surprised when we discovered there does seem to be a link. We found that with each cup of tea drank above seven cups, the bigger the risk of you catching the cancer.
We don't know whether tea itself is a risk factor or if tea drinkers are generally healthier and live to an older age when prostate cancer is more common anyway.”
The Tea Advisory Panel
has called the research flawed. Nutritionist Dr. Carrie Ruxton, a member of the panel, said “
The study doesn't show a cause and effect relationship between tea drinking and cancer risk. Tea drinking is simply a marker for some other issue. That may be down to issues with stress, or perhaps diet.”