Folic acid levels are high enough in most people -- except the right people

Folic acid has been added to grain products for more than a decade in order to boost intake among women of reproductive age. The supplementation was endorsed after studies showed adequate levels of folic acid are necessary to prevent spinal cord defects and other birth defects. But a new study suggests everyone except reproductive age women are getting plenty of the nutrient.

Researchers in Canada examined the folate status of Canadians of all ages. Like the United States, Canada adds folic acid to grain products. More than 5,000 people were tested for their folate status. The study found that less than 1% of Canadians had a deficiency while 40% had high concentrations. Among reproductive-age women, 22% had levels that were below what is considered optimal to prevent birth defects.

The study is somewhat alarming because the target group -- young women -- aren’t getting the full benefit of supplementation while others get too much. Some studies have suggested that too-high levels of folic acid can be harmful to some people, increasing the risk of certain cancers.

The authors, researchers from Children’s Hospital of Eastern Ontario Research Institute and the Hospital for Sick Children in Toronto, concluded: “...further attempts to improve the folate status of Canadian women of childbearing age by increasing fortification levels should be approached cautiously.”

The study was published Monday in the Canadian Medical Assn. Journal.

Related: Folic acid and cancer: New data might add to suspicion or, better, to discussion

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