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Can folate supplements be dangerous? - part 1

In a nutshell

Concerns have been raised over potential adverse effects of folic acid supplements, particularly in countries where food is fortified with folic acid. The concerns include masking B12 deficiency, increased risk of multiple birth, allergic disease, and the appearance of unmetabolised folic acid in the blood.

At this point in time we lack solid evidence that any of these is a significant practical clinical problem, although neither has it been ruled out that some individuals might be affected.

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References

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