Vitamin E and minerals may slash bladder cancer risk

January 08, 2010

     Increased intakes of vitamin E may reduce the risk of bladder cancer by about 35 per cent, says a new study from an international team of researchers. Their research also shows that carotenoids, the B-Complex Vitamins Niacin and Thiamine, and vitamin D may reduce the risk of bladder cancer in older people. “The effects of vitamin E, carotenoids, vitamin D, thiamine and niacin in relation to the risk of developing bladder cancer may warrant further investigation,” report the researchers, led by Maree Brinkman from The Cancer Council Victoria in Australia. “Future studies should focus on optimal doses and combinations of these micronutrients particularly for high risk groups such as heavy smokers and older individuals,” they state. Bladder cancer is diagnosed in about 336,000 people every year worldwide, and it is three times more likely to affect men than women, according to the European School of Oncology.
     Dr. Brinkman and her co-workers analysed dietary data from 322 people with bladder cancer and 239 healthy controls. A 121-item food frequency questionnaire was used to estimate dietary intakes. Results showed that, in general, people with the highest average intakes of vitamin E (at least 193.4 milligrams per day) were 34 % less likely to develop bladder cancer. When the researchers focused their analysis on smokers because they are people at much higher increased risk of developing bladder cancer, they found that the highest intakes of vitamin E, Carotenoids (18 milligrams), and Niacin (46.5 milligrams), were associated with a 42 % (Vitamin E), 38 % (Carotenoids), and 34 % (Niacin) reduction in bladder cancer risk in heavy smokers. In older individuals, the highest average intakes of Carotenoids, Vitamin D (641 International Units), Thiamine (3.35 milligrams), Niacin, and Vitamin E were all associated with a reduced bladder cancer risk.
     “Bladder cancer is a disease that typically affects older people, and bioavailability of B-group vitamins may be compromised in this demographic by certain drugs (e.g., acid lowering agents),” stated the researchers. “Additionally, vitamin E, like carotenoids acts as an antioxidant and, as suggested by our results, could be more beneficial under conditions of the greatest oxidative stress such as smoking and aging.” The researchers called for additional study to further examine these potentially protective relationships.
The study was supported by the National Institute of Environmental Health Sciences and the National Cancer Institute at the US National Institutes of Health (NIH) and is published online ahead of print in the journal Cancer Causes and Control.