Can you take magnesium while pregnant?

Can you take magnesium while pregnant?

Yes, magnesium is generally safe to take during pregnancy and is, in fact, an important mineral for both you and your developing baby. Many prenatal vitamins already contain some magnesium, though the amount varies widely between brands.

Magnesium plays a role in over 300 enzymatic reactions in the body. During pregnancy, your need for it increases to support fetal bone development, muscle function, and nerve signaling. The recommended dietary allowance (RDA) for magnesium during pregnancy is 350 to 360 mg per day, depending on your age.

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What does the research say?

A Cochrane systematic review on magnesium supplementation in pregnancy evaluated multiple randomized controlled trials and found that magnesium supplementation may be associated with a lower risk of fetal growth restriction and preterm birth, though the authors noted that the quality of evidence was mixed and more research is needed.

A 2022 meta-analysis in Food Science & Nutrition examining magnesium supplementation in gestational diabetes patients found that magnesium improved fasting plasma glucose and insulin resistance markers.

Which form of magnesium is best during pregnancy?

The form matters. Magnesium glycinate is often recommended for pregnancy because of its high bioavailability and gentle effect on digestion. Magnesium oxide, while common, is poorly absorbed (as low as 4% bioavailability) and more likely to cause loose stools. Magnesium citrate falls somewhere in between and may have a mild laxative effect, which can actually be helpful if constipation is an issue.

How much should you take?

Stick to the RDA unless your healthcare provider advises otherwise. The tolerable upper intake level for supplemental magnesium (from supplements, not food) is 350-400 mg per day for pregnant adults. Going above this without medical supervision can lead to diarrhea, nausea, or in rare cases, more serious concerns.

Keep in mind that magnesium from food sources (leafy greens, nuts, seeds, whole grains) counts toward your daily needs and does not carry the same risk of overdoing it.

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A note from WeNatal on magnesium supplementation during pregnancy

WeNatal Rest + Digest Magnesium focuses on magnesium glycinate, the form most recommended during pregnancy for its superior absorption and gentle stomach profile. Paired with WeNatal for Her, it helps round out your prenatal nutrition. As always, check with your provider before adding any new supplement to your routine.

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References

Fanni D, et al. (2021). The role of magnesium in pregnancy and in fetal programming of adult diseases. Biological Trace Element Research, 199:3647-3657. DOI: 10.1007/s12011-020-02513-0

Makrides M, et al. (2014). Magnesium supplementation in pregnancy. Cochrane Database of Systematic Reviews, 4:CD000937. DOI: 10.1002/14651858.CD000937.pub2

Qu X, et al. (2022). Effect of magnesium supplementation on pregnancy outcome in gestational diabetes mellitus patients: A meta-analysis. Food Science & Nutrition, 10(10):3193-3202. DOI: 10.1002/fsn3.2561