HELSINKI, FINLAND. It is estimated that 172,000 new cases of lung cancer would be diagnosed in the US in 1999. The survival rate for lung cancer victims is very poor so preventive measures are of utmost importance. A team of researchers from the National Cancer Institute in the US and the National Public Health Institute in Finland now reports that men who have high blood levels of vitamin B6 (pyridoxine) are much less likely to develop lung cancer than are men with lower levels.
The study was part of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention
Study and involved 300 male smokers with lung cancer and 300 healthy controls
(also smokers). All the participants had their blood serum levels of folic
acid, vitamin B6, vitamin B12, and homocysteine measured. No significant
differences in folic acid, vitamin B12 and homocysteine levels were noted
between the two groups. However, after adjusting for body mass index, years of
smoking, and the number of cigarettes smoked a day the researchers noted a very
significant protective effect of vitamin B6. The men with a serum level above
35 nmol/L had about half the risk of lung cancer than did the men with a level
at or below 20.6 nmol/L. The researchers also found that 54 per cent of all
study participants (cases and controls) were deficient in vitamin B6, 90 per
cent were deficient in folic acid, and 25 per cent had elevated serum
homocysteine levels. They speculate that vitamin B6's protective effect is
related to its known immune system enhancing effects and its key role in the
synthesis of the important antioxidant glutathione.