Pleasant Stone Farm Clinical Reports

Higher blood levels of vitamin B6 may reduce the risk of lung cancer by about 50 per cent, says a new analysis of almost 400,000 people, including current and former smokers.

Researchers also report that the amino acid methionine, which is found in most protein, may also reduce the risk of lung cancer.

“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,” wrote the authors in the Journal of the American Medical Association.

One in three Europeans are smokers, while the US figure is one in five. Tobacco smoke contains over 4,000 compounds, of which 60 are known carcinogens. The oxidative stress levels of smokers are significantly greater than non-smokers, and as such there is a bigger drain on the levels of antioxidants in the body.

Furthermore, the new study indicated that folate may also be beneficial, and that high folate levels combined with methionine and B6 were associated with a 66 per cent reduction in lung cancer risk.

Study details

Led by Paul Brennan from the International Agency for Research on Cancer in Lyon, France, the researchers used data from 385,747 people who donated blood while participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). Out of this, 899 people with lung cancer were identified and matched with 1,770 cancer-free people.

The researchers noted that increasing blood levels of vitamin B6 were associated with lower risks of lung cancer. A similar risk reduction was observed for methionine, which extended to never, former, and current smokers. This indicated that smoking habits were not confounding the results.

“Our results suggest that above-median serum measures of both B6 and methionine, assessed on average 5 years prior to disease onset, are associated with a reduction of at least 50 percent on the risk of developing lung cancer,” wrote the researchers. “An additional association for se­rum levels of folate was present, that when combined with B6 and methionine, was associated with a two-thirds lower risk of lung cancer,” they added.

More research needed

Correlation does not prove causation, however, and more research is needed to clarify the role of B vitamins and methionine in lung cancer, said the researchers.

“It is essential that for lung cancer prevention, any additional evidence about causality does not detract from the importance of reducing the numbers of individuals who smoke tobacco,” wrote Brennan and his co-workers

“With this in mind, it is important to recognize that a large proportion of lung cancer cases occur among former smokers, making up the majority in countries where tobacco campaigns have been particularly successful, and a non-trivial number of lung cancer cases oc­cur also among never smokers, particu­larly among women in parts of Asia.

“Clarifying the role of B vitamins and re­lated metabolites in lung cancer risk is likely therefore to be particularly relevant for former smokers and never smokers,” they concluded.

Authors: JAMA
2010, Volume 303, Number 23, Pages 2377-2385
“Serum B Vitamin Levels and Risk of Lung Cancer”
Authors: M. Johansson, C. Relton, P.M. Ueland, et al.

A low-risk lifestyle and diet will lead to less instances of hypertension in women, and cost less than pharma remedies, according to a study published in the Journal of American Nutrition (JAMA).

The 20-year cohort study followed more than 83,000 healthy nurses from a pool of about 116,000 who filled out questionnaires every two years and which found significant reductions in self-reported hypertension occurred better when diets and lifestyles were pursued.

Hypertension is thought to be the biggest contributor to preventable death in the US among women.

The researchers found only 37 per cent of women with hypertension had controlled blood pressure compared to 57 per cent taking pharmaceutical treatments.

“Primary prevention of hypertension, therefore, would have major positive public health ramifications,” the researchers wrote.

Factors leading to hypertension included obesity; alcohol and tobacco use and dietary factors such as low folic acid intake.

Low-risk factors for hypertension were a Body mass Index (BMI) of less than 25; an average of 30 minutes exercise per day; a good diet as measured by the Dietary Approaches to Stop Hypertension (DASH); alcohol intake of less than 10g per day; use of nonnarcotic analgesics once per day; and intake of at least 400ug per day of folic acid per day.

Over the 20 year period, 12,319 hypertension cases were detected among the population of 27 to 44-year-old nurses – or approximately 15 per cent of the population.

Younger nurses who took more than 1000ug/d of folic acid were found to have 46 per cent less chance of developing hypertension, 18 per cent for older nurses.

Among women who had negligible dietary intake of folic acid in their regular diets, supplementation was shown to significantly reduce hypertension risk.