Researchers have found that higher vitamin B6 levels is linked with a 50 per cent reduction in the risk of developing lung cancer in a study involving over 400,000 people, including former and current smokers. Also, high levels of methionine, an amino, also contributes to a lower risk.
The study authors wrote in the Journal of the American Medical Association, “Given their involvement in maintaining DNA integrity and gene expression, these nutrients have a potentially important role in inhibiting cancer development, and offer the possibility of modifying cancer risk through dietary changes.
In the US, 20 per cent of the population are smokers, while 33 per cent of Europeans are. In the U.S. alone, more than 219,000 new cases of lung cancer were expected in 2009, according to the American Cancer Society, with about 160,000 deaths.
The study, funded by the World Cancer Research Fund and others.
The research was led by Paul Brennan of the International Agency for Research on Cancer, located in Lyon, France. The researchers evaluated dated from blood donor participants in the European Prospective Investigation into Cancer and Nutrition. Almost 900 people with lung cancer were identified and matched with 1770 cancer free people. They were matched by date of birth, gender and country at the time of the blood collection. Based on their vitamin B6 levels, the participants were placed into four groups. Vitamin B6, helps cells to break down protein, stabilizes red blood cells, and participates in other bodily functions.
Their results suggests that above average levels of vitamin B6 and methionine, measured 5 years before the disease developed lowers the risk of developing lung cancer. And a similar phenomena was observed for methionine, which included nonsmokers, former and current smothers. People in the highest group for vitamin B levels had a 56% reduced lung cancer risk, compared to those in the lowest group. Those with the highest methionine levels had a 48% reduced lung cancer risk, the researchers found.
”That’s quite a strong effect,” Brennan says, but emphasizes that more study is needed. Some previous research, he says, looked only at smokers and linked vitamin B6 to a reduced lung cancer risk. His study, by including never smokers and past smokers, expands the information about the link.
Vitamin B 6 is found in meat, fish, poultry, grains, beans, some vegetables and fruit. Methionine occurs in some nuts, vegetable seeds and animal protein. The manner in which vitamin B6 acts on the cells is not clear, but its deficiency may increase the risk of DNA damage that plays a part in cancer development. Brennan acknowledges that it is most important for smokers to quit, since it’s the main risk factor for lung cancer, rather than taking a supplement.
Johansson M, et al “Serum B vitamin levels and risk of lung cancer” JAMA 2010; 303(23): 2377-85.