How much folic acid is safe to take?

It is safe to take as much as 1,000 micrograms of folic acid, the synthetic form of folate, in fortified foods and supplements. That's more than twice the recommended dietary allowance of 400 micrograms.

Since a multivitamin may contain as much as 800 micrograms of folic acid, you could easily exceed this daily upper limit if you also often eat heavily fortified foods like energy bars and cold cereals. Read labels carefully and do the math.

The danger in taking too much folic acid is that it can hide a vitamin B12 deficiency. Older people are vulnerable to a B12 shortfall and need to be particularly careful about how much folic acid they take. 
Janis Jibrin, MS, RD
Nutrition & Dietetics
Most multivitamins contain 400 microgram (mcg) of folic acid, so to be safe, you may want to take a multivitamin every other day if you're a postmenopausal woman or a man of any age. Also, be sure to examine any fortified food carefully to make sure you're not getting too much folic acid from those sources on the day you take your vitamin. As for food sources of folate, keep eating them; they're not linked to any risk.

If you are a premenopausal woman who's even considering becoming pregnant, it's crucial that you get 400 mcg of folic acid every single day via your multi. It may be even more important to get enough of this vitamin before and during conception than afterward.
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.