I have taken folic acid off and on over the last few years - I can't seem to make up my mind. It is obviously extraordinarily important for pregnant women. It has also been recommended for anyone who drinks - alcohol supposedly depletes it. It also has other anti-oxidant values. But now I have definitely decided against taking it. Here's why:
Scientists question folic acid fortification
Scientists at the Institute of Food Research have highlighted possible consequences of fortifying flour with folic acid due to new evidence of how it is absorbed by the body.
In May, the Food Standards Agency’s Board agreed unanimously that 'mandatory fortification' with folic acid should be introduced to make sure the number of babies born with neural tube defects is reduced. This means that it would be compulsory to add folic acid to either bread or flour.
Folic acid is a synthetic form of folate, a B vitamin found in a wide variety of foods including liver and green leafy vegetables. Folates are metabolised in the gut, whereas in a paper to be published in the British Journal of Nutrition in October IFR scientists suggest that folic acid is metabolised in the liver. The liver is an easily saturated system, and fortification could lead to significant unmetabolised folic acid entering the blood stream, with the potential to cause a number of health problems.
“Fortifying UK flour with folic acid would reduce the incidence of neural tube defects”, said Dr Siân Astley of the Institute of Food Research. “However, with doses of half the amount being proposed for fortification in the UK, the liver becomes saturated and unmetabolised folic acid floats around the blood stream.
“This can cause problems for people being treated for leukaemia and arthritis, women being treated for ectopic pregnancies, men with a family history of bowel cancer, people with blocked arteries being treated with a stent and elderly people with poor vitamin B status. For women undergoing in-vitro fertilisation, it can also increase the likelihood of conceiving multiple embryos, with all the associated risks for the mother and babies.
“It could take 20 years for any potential harmful effects of unmetabolised folic acid to become apparent”.
It has already been shown that folic acid forticifation can exhibit Jekyll and Hyde characteristics, providing protection in some people while causing harm to others. For example, studies have confirmed that unmetabolised folic acid accelerates cognitive decline in the elderly with low vitamin B12 status, while those with normal vitamin B12 status may be protected against cognitive impairment. Most over 65s in the UK have low B12 status.
Similarly, dietary folates have a protective effect against cancer, but folic acid supplementation may increase the incidence of bowel cancer. It may also increase the incidence of breast cancer in postmenopausal women.
Since the 1980s a consensus formed that that folic acid is metabolised in the small intestine in a similar way to naturally-occuring folates. This consensus was used to assess the safety of folic acid fortification.
"We challenge the underlying scientific premise behind this consensus", said Dr Astley. "This has important implications for the use of folic acid in fortification, because even at low doses it could lead to over consumption of folic acid with its inherent risks".
Folic Acid Linked to Increased Cancer Rate
Two recent commentaries appearing in the November issue of Nutrition Reviews find that the introduction of flour fortified with folic acid into common foods was followed by an increase in colon cancer diagnoses in the U.S. and Canada. The two new review articles address these recent findings and provide an overview of the existing evidence on folic acid fortification and the associated policy issues.
For nearly a decade, folic acid, a chemical form of a common B vitamin (folate), has been added to wheat flour and other grain products in the U.S. and Canada. This public health measure was enacted after evidence was discovered linking folic acid with a reduced rate of a specific birth defect that affected the development of the spinal cord and central nervous system. During the same period, however, rates of colorectal cancer in the U.S. inexplicably began rising, even as regular colonoscopy check-ups became more common. In Canada, where folic acid supplementation was introduced a bit later, the same trend has been observed.
Dr. Solomons, author of one of the review commentaries, “Food Fortification with Folic Acid: Has the Other Shoe Dropped?” advises that a careful reconsideration of the fortification program is needed. “One size of dietary folic acid exposure does not fit all. It can be beneficial to some and detrimental to others at the same time,” comments Solomons.
Since the risk-benefit value of fortification varies according to age, Solomons suggests a reevaluation of the manner in which folic acid to prevent birth defects is delivered to the public. Among other things, targeting women of reproductive age while reducing folic acid levels in foods for which fortification is optional (such as ready-to-eat cereals and commercial drinks), would be worthy of consideration, in the opinion of Solomons.
As a result of noted birth defect reduction, 42 countries have implemented some form of mandatory folic acid fortification. The two commentaries stress the need to carefully consider and balance the risks and benefits associated with introducing such a program.
“Folic acid supplementation wields a double-edged sword,” remarks Dr. Young-In Kim, author of “Folic Acid Fortification and Supplementation—Good for Some but Not So Good for Others,” the other commentary review published in the November issue. According to Kim, “It may be beneficial or harmful, depending on the timing of intervention.” Exposure to high intakes of folic acid in early life and young adulthood may provide life-long protection from the tendency for cancer formation in different organs, such as the large intestines, whereas such exposures later in life, when cell damage has occurred, can spur on the advance of the tumor.
What is folate and why do you need it?
Janice Hermann, Oklahoma State University Cooperative Extension nutrition specialist, said folate is a water-soluble vitamin that helps make the genetic material in every cell, works with vitamin B12 to make red blood cells, assists in preventing neural tube defects – such as spina bifida in infants – and may help protect against heart disease.
“If you have a low intake of folate, you may have anemia, weakness and fatigue,” she said. “Not consuming enough folate, before and early in pregnancy, may increase the risk of having an infant with neural tube defects.”
Good sources of folate include liver, legumes, green-leafy vegetables and citrus fruits and juices. Many breads, cereals and grain products also are fortified with folate.
Hermann said folate can be lost from foods during preparation, cooking or storage. To keep from losing folate she recommends serving fruits and vegetables raw when possible; steam, boil or simmer vegetables in a minimal amount of water and store vegetables in the refrigerator.
“Eating a wide variety of foods that contain folate is the best way to get sufficient intakes,” she said. “A folate supplement is often recommended for women one month before getting pregnant and through the first trimester to lower the risk of neural tube defects.”
The daily recommendations for folate are:_• Men 19 years and older; 400 micrograms per day._• Women 19 years and older; 400 micrograms per day._• Women who are pregnant 600 micrograms per day._• Women who are breastfeeding 500 micrograms per day.
Because excess folate can mask symptoms of vitamin B12 deficiency, a Tolerable Upper Intake Level of 1,000 micrograms per day has been established for folate from fortified foods or supplements.
Vitamin B and folic acid may reduce risk of age-related vision loss
Taking a combination of vitamins B6 and B12 and folic acid appears to decrease the risk of age-related macular degeneration in women, according to a report in the February 23 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Age-related macular degeneration (AMD) is a leading cause of vision loss in older Americans, according to background information in the article. Treatment options exist for those with severe cases of the disease, but the only known prevention method is to avoid smoking. Recent studies have drawn a connection between AMD and blood levels of homocysteine, an amino acid. High levels of homocysteine are associated with dysfunction of the blood vessel lining, whereas treatment with vitamin B6, vitamin B12 and folic acid appears to reduce homocysteine levels and may reverse this blood vessel dysfunction.
William G. Christen, Sc.D., of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues conducted a randomized, double-blind clinical trial involving 5,442 women age 40 and older who already had heart disease or at least three risk factors. Of these, 5,205 did not have AMD at the beginning of the study. In April 1998, these women were randomly assigned to take a placebo or a combination of folic acid (2.5 milligrams per day), pyridoxine hydrochloride (vitamin B6, 50 milligrams per day) and cyanocobalamin (vitamin B12, 1 milligram per day). Participants continued the therapy through July 2005 and were tracked for the development of AMD through November 2005.
Over an average of 7.3 years of treatment and follow-up, 137 new cases of AMD were documented, including 70 cases that were visually significant (resulting in a visual acuity of 20/30 or worse). Of these, 55 AMD cases, 26 visually significant, occurred in the 2,607 women in the active treatment group, whereas 82 of the 2,598 women in the placebo group developed AMD, 44 cases of which were visually significant. Women taking the supplements had a 34 percent lower risk of any AMD and a 41 percent lower risk of visually significant AMD. "The beneficial effect of treatment began to emerge at approximately two years of follow-up and persisted throughout the trial," the authors write.
"The trial findings reported herein are the strongest evidence to date in support of a possible beneficial effect of folic acid and B vitamin supplements in AMD prevention," the authors write. Because they apply to the early stages of disease development, they appear to represent the first identified way—other than not smoking—to reduce the risk of AMD in individuals at an average risk. "From a public health perspective, this is particularly important because persons with early AMD are at increased risk of developing advanced AMD, the leading cause of severe, irreversible vision loss in older Americans."
Beyond lowering homocysteine levels, potential mechanisms for the effectiveness of B vitamins and folic acid in preventing AMD include antioxidant effects and improved function of blood vessels in the eye, they note.
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