Men who drink more than seven cups of tea a day may be increasing their chances of developing prostate cancer, says a new study.
"We found that heavy tea drinkers were more likely not to be overweight, be non-alcohol drinkers and have healthy cholesterol levels. However, we did adjust for these differences in our analysis and still found that men who drank the most tea were at greater risk of prostate cancer," said Dr. Shafique, the lead author of the study, to The Press Association.
The research included more than 6,000 men from Scotland. All aged between 21 and 75.
The participants were asked to complete a questionnaire regarding their health, lifestyle that included consumption of coffee, tea, alcohol and smoking. They also had to undergo screening examination.
Almost a quarter of all men in the study group had reported that they were heavy drinkers.
The researchers found that prostate cancer risk in men who drank more than 7 cups of tea per day was about 50 percent more than people who drank limited amounts of tea.
6.4 percent of men who were heavy tea drinkers developed prostate cancer during the 37 year follow up.
"There has been much interest in the preventive effects of green tea on prostate cancer risk; however, we found a harmful effect of black tea on prostate cancer risk. The association between tea intake and prostate cancer should be investigated in prospective epidemiological studies in relation to different compositions of tea," the researchers said to The Press Association.
Experts say that there might have been other factors associated with the development of prostate cancer in the group that the research did not study.
"Whilst it does appear that - of the 6,000 men who took part in this study - those who drank seven or more cups of tea each day had an increased risk of developing prostate cancer, this did not take into consideration family history or any other dietary elements other than tea, coffee and alcohol intake," Dr. Kate Holmes, head of research at the Prostate Cancer charity told BBC.
Prostate cancer is the most common type of cancer in men. The Centers for Disease Control and Prevention says that in 2008, 214,633 men were diagnosed with prostate cancer, and 28,471 men died from the cancer.
Moderate tea drinking may not have any negative effects.
"We would therefore not wish any man to be concerned that drinking a moderate amount of tea as part of a healthy diet will put them at an increased risk of developing prostate cancer," Dr. Holmes said, reports BBC.
The study is published in the journal Nutrition and Cancer.