Supplemental Folic Acid in Late Pregnancy Associated with Childhood Asthma

In yet another study assessing the impact of folic acid supplementation in pregnancy, Australian researchers have found an association between use of folic acid supplements in late pregnancy and the risk for asthma in childhood. The risk was not found with use of folate when it was confined to the prenatal period and the first trimester of pregnancy, a time when its use decreases the incidence of neural tube defects such as spina bifida. Intake of folate from dietary sources was also not associated with childhood asthma.

The study is quite muddied with confounding variables, imperfect data sources and no data on supplement use in childhood. Still it raises important concerns, and if its findings are replicated in other studies, it would suggest that folic acid supplementation should be limited to the prenatal and first trimesters. It’s also important not to exceed current dosing recommendations for this important vitamin.

It also underscores what I’ve been telling my patients for years – it’s always preferable to get your vitamins from dietary sources rather than supplements.

5 Responses to Supplemental Folic Acid in Late Pregnancy Associated with Childhood Asthma

  1. I think you may have a typo:

    "a time when is use decreases the incidence of neural tube defects such as spina bifida"

    which you may want to correct.

    Great blog! Thank you.

  2. I wish more doctors were like you. I've mentioned these studies to my PCP and OB (who are vitamin pushers), and neither knew about them, nor changed their position. They've called in about a billion prescriptions for these overpriced, over marketed vitamins (I still have those damn drug rep giveaways, somewhere) even though I refuse to take them. It's one of the reasons I'm having a home birth, but that's OT.

  3. My husband had a bone marrow transplant last year and that's exactly what his Oncology team told him – no vitamins, no supplements – eat a good diet.

    It's the perfect excuse for throwing a box of those $8 clementine oranges into your cart.

  4. well, thanks for the post it is really knowledgeable post….i was unaware of the Pregnancy Associated with childhood Asthma

Leave a Reply