Higher Blood Levels of Vitamin B6 and Methionine Lowers Risk of Lung Cancer!!!

Lung cancer is a disease that forms in tissues in one or both lungs and usually in the cells lining the air passages. The majority of lung cancers are malignancies that arise from epithelial cells. Lung cancers most commonly metastasis to the adrenal glands, liver, brain and bone. There are two types of lung cancer; one being small cell lung cancer and the other one being non-small cell lung cancer. Cigarette smoking causes most lung cancers but high levels of pollution, radiation and asbestos exposure may also increase the risk. Statistical estimates in the US for 2008 including both types of lung cancer would be 215,020 new cases and 161,840 deaths.

Vitamin B6 (pyridoxine) is a water soluble vitamin that is instrumental in more than 100 enzyme reactions in the body. These activities are mostly related to the metabolism of amino acids and proteins. Vitamin B6 deficiency is one of the most common nutritional deficiencies. Much of this is due to the fact that a lot of vitamin B6 is lost during cooking and food processing. A U.S. Department of Agriculture study reported that 80 percent of Americans consume less than the recommended dietary allowance (RDA) for vitamin B6.

Methionine is the only amino acid that forms sulfide bonds in proteins. It is important to a variety of biochemical pathways; most cells can use homocysteine as a substitute for methionine. However, there are methionine-dependent cells that cannot use homocysteine in place of methionine. Methionine levels affect the amount of sulfur-containing compounds, such as glutathione, which defend against toxic compounds, in the liver. When higher levels of toxic compounds are present, more methionine is needed.

Current research has found that higher blood levels if vitamin B6 and methionine reduce the risk of lung cancer. The study included 519,978 participants from ten countries between 1992 and 2000. In 2006, a total of 899 cases of lung cancer had been identified and 1,770 control participants were selected and matched based on country, sex, age and date of blood collected. The results revealed that increasing blood levels of vitamin B6 were associated with lower risk of lung cancer. A similar risk reduction was also observed for methionine, which extended to never, former and current smokers. These findings suggest that above average blood levels of vitamin B6 and methionine, assessed on average 5 years prior to disease onset, are associated with at least a 50 percent reduction in the risk of developing lung cancer. The researchers also noted that when higher levels of vitamin B6 and methionine are combined with an increased level of folate the reduction in lung cancer is 66 percent. This correlation does not prove causation, however, and more research is needed to clarify the role of B vitamins and methionine in lung cancer.1

1 Johansson M, Relton C, Ueland PM, et al. Serum B vitamin levels and risk of lung cancer. JAMA. Jun2010;303(23):2377-85,