Entries tagged with “folate”
Jul
15
2010
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.
Jun
29
2010
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.
Apr
30
2010
The development of a child’s brain in early pregnancy may be impaired by low folate levels in the mother, and lead to behavioural problems such as hyperactivity and inattention, says a new study.
Low folate levels in early pregnancy were associated with increased rates of childhood hyperactivity and peer problems, according to a study with 100 mothers and their children followed for almost nine years.
Scientists from the University of Southampton and University College London’s Institute of Child Health propose that the low folate levels impair the development of the brain in the foetus, and early pregnancy is a critical time for brain development.
“To our knowledge, this is the first study in humans to provide evidence for associations of maternal folate with behavioural outcomes in the offspring, and it is the first study to demonstrate a putative pathway via foetal head growth,” wrote the researchers in the Journal of Child Psychology and Psychiatry.
B for baby benefits
An overwhelming body of evidence links folate deficiency in early pregnancy to increased risk of neural tube defects (NTDs) – most commonly spina bifida and anencephaly – in infants. Most NTDs occur within the first 22 to 28 days of pregnancy, when the mother-to-be is not aware she is even pregnant.
Folic acid supplements after this time are too late to prevent neural tube defects and therefore fail to benefit women with unplanned pregnancies – more than half of all pregnancies in the US.
This connection led to the 1998 introduction of public health measures in the US and Canada, where all grain products are fortified with folic acid – the synthetic, bioavailable form of folate.
Preliminary evidence indicates that the measure is having an effect with a reported 15 to 50 per cent reduction in NTD incidence. A total of 51 countries now have some degree of mandatory fortification of flour with folic acid.
However, similar measures in other countries, including the UK where the new study was based, have been opposed by concerns that the folate/folic acid may mask vitamin B12 deficiency, which leads to a form of neurological problems.
Study details
Led by Southampton’s Dr Wolff Schlotz, the researchers recruited 100 mothers in early pregnancy and took blood samples to measure folate levels, and the followed them for an average of 8.75 years. The mothers reported on their children’s behaviour using the Strengths and Difficulties Questionnaire.
The results showed that low maternal levels of folate were associated with both higher childhood hyperactivity and peer problems scores.
“Although the associations are small and residual confounding is possible, our data provide preliminary support for the hypothesis that lower folate status in early pregnancy might impair foetal brain development and affect hyperactivity/inattention and peer problems in childhood,” wrote Dr Schlotz and his co-workers.
Dutch researchers reported in the British Journal of Nutrition in September 2009 that the children of mothers who took folic acid supplements during pregnancy were better at internalising and externalising problems, compared to the children of mothers who did not take supplements.
Source: Journal of Child Psychology and Psychiatry
May 2010, Volume 51, Issue 5, Pages: 594-602
“Lower maternal folate status in early pregnancy is associated with childhood hyperactivity and peer problems in offspring”
Authors: W. Schlotz, A. Jones, D.I.W. Phillips, C.R. Gale, S.M. Robinson, K.M. Godfrey