"As a result of a federal program requiring some foods to be fortified with folic acid, nearly half the population now consumes high amounts of the vitamin, which may put some at risk of cancer." So states the Globe and Mail, December 14th, 10. But this is not what the Canadian researchers concluded.
I give credit to the authors of the study published Dec. 13th in the CMAJ. They say:
"The purpose of our study was to investigate the folate status of a nationally representative sample of Canadians, including a subset of women of childbearing age. Read it here:http://www.canadianmedicaljournal.ca/cgi/content/abstract/cmaj.100568v2
They conclude:
- There is virtually no folate deficiency in Canada.
- Young women of child bearing age, even though they had normal levels of RBC folate, were not supplementing enough in their diet and added supplements to get folate levels above 900, the level determined to prevent NTD.
- There should be on going monitoring of folate status and health outcomes.
Interesting study, and I fully agree there should be more studies on the relationship of folic acid, folate and health. I would hate it if this study discouraged any one from taking good quality B vitamens with folate( not folic acid) and B12, because I've seen so much benefit from these. Men and boys have benefited too. Folate helps the body produce healthy red blood cells, guards against neural tube defects such as spina bifida and performs a range of other functions including lowering cancer rates.
I find it so frustrating and difficult to assess any original research, when so many use folate and folic acid interchangeably. They are not the same.
This is what I've learned about folic acid and folate.
Folic acid (synthetic) has to be converted by MTHFR enzymes to folate, and folinic acid and folate are what is used in our metabolism. Folate is what is usually measured to determine folate status. We vary in our genetics in our ability to convert folic acid to folate. If you have MTHFR alleles or variations of these genes, then there is a back log of folic acid waiting to be metabolized, which may be giving high levels of folic acid. How much? Nobody knows. A new study published in the Proceedings on the National Academy of Sciences (PNAS) shows that our ability to convert folic acid to folate may be relatively slow, leading to extended exposure to unconverted folic acid. Is unconverted folic acid safe? Studies show that small amounts may be safe and more is not.
Some studies of folic acid supplementation have been linked to slight elevations in cancer rates. They are not considered well done studies. There have been over 30 studies that have shown reduced rates of cancer with the supplementation of folic acid.
Reference 1, the Norway study mentioned by the Globe and Mail on December 14th, found higher rates of lung cancer in older male heart disease patients, and some say the study actually showed the dangers of smoking, not of folic acid supplementation. A Harvard study in 2009, showed that supplements of folic acid helped and reduced the recurrence of colorectal cancer in people with low levels of the nutrient, but not people who already have adequate amounts. There was no elevation of cancer rates. ( Reference 2)
Back to the new study, I disagree with the second line in the "Background " section of their article where they caution "high folate concentrations may be associated with adverse outcomes, including increased risk of colorectal cancer among those with pre-existing neoplasms." in that all the studies that have shown increased cancer rates have been looking at folic acid supplementation and not folate status. The Canadian study published in 2009 linked folic acid supplementation( especially from enriched grains) with higher colon cancer rates. But this can be explained by higher rates of diagnosis of earlier colon cancer because of the major colon cancer screening program started about five years ago. Time will tell if there is actual increases in the incidence of colon cancer.
And, at present there have been no published studies showing that supplementation with "natural identical" folates such as 5-methyltetrahydrofolate or 5-formyltetrahydrofolate enhances the progression of pre-existing neoplasms. That means they are safe.
I also am suspicious of their conclusion that "Folate deficiency is virtually nonexistent in the Canadian population". They use the guideline for folate deficiency as red blood cell folate less than 305 nmol/L but with further studies we could find out that health promotion is accomplished when higher levels are maintained.
We desperately need more studies on the relationship of folic acid, folate and good health. Linus Pauling had strong opinions on the health promoting effects of folate.
Supplementing with folate has been shown to promote wellness with less cancer, less depression, less cardiac disease. We may find out the artificial folic acid is good in small amounts and not so good in larger amounts and that the amounts fortifying our grain foods now, is safe for the majority of persons and a great benefit to pregnant women to build a better baby.
Everything points to you being better off if you have some folic acid.
You are probably wondering: how much?
If you are going to take more folic acid than what is in your food, then it should come from a natural source folate such as is found in AOR's Advanced B Complex or in Metagenics Folapro. Or speak to your health care professional who may know another source.
To your Health
Dr. Barbara
References:
1.Ebbing M, et al "Cancer incidence and mortality after treatment with folic acid and vitamin B12" JAMA 2009; 302: 2119-26.
2. American Journal of Clinical Nutrition Published online ahead of print, doi:10.3945/ajcn.2009.28319
“A randomized trial on folic acid supplementation and risk of recurrent colorectal adenoma”
Authors: K. Wu, E.A. Platz, W.C. Willett, C.S. Fuchs, J. Selhub, B.A. Rosner, D.J. Hunter, E. Giovannucc
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