“Can you take magnesium while pregnant?” is a question we often hear at Thorne, and with good reason as magnesium is involved in hundreds of reactions in the body and is an essential mineral for human health. However, “Should you take magnesium during pregnancy?” is a question best answered in collaboration with your health-care practitioner. 

As always, it’s a good idea to discuss any supplement you are taking, or you are considering taking, with a trusted health-care practitioner. This is especially true for individuals who are pregnant, breastfeeding, or trying to conceive.

For general information about magnesium and magnesium supplements during pregnancy, continue reading. We will explore several magnesium and pregnancy FAQs, such as, “Is magnesium safe during pregnancy?”, “Can you take magnesium while pregnant?” and “How much magnesium can you take while pregnant?”

But first, let’s start with some magnesium basics. 

Magnesium is one of the most abundant minerals found in the Earth’s crust. It is naturally present in many foods and can be found throughout the human body. Much of the magnesium in the body is present in the bones, and it is also found in lesser amounts in the soft tissues. Adult bodies contain about 25 g of magnesium.1,2

Green leafy vegetables, whole grains, beans, seeds, and nuts are the best food sources of naturally occurring magnesium. Yet based on dietary data, including dietary surveys from the National Health and Nutrition Examination Survey (NHANES), it is estimated that about half of the adults in the United States do not consume enough magnesium to meet nutritional needs.1,2

Magnesium is necessary for the proper function of many biochemical reactions in the body, all the way down to the creation of the tiniest building blocks – DNA and RNA. Bone structure, muscle relaxation, nerve conduction, blood sugar regulation, and even the creation of the antioxidant glutathione all require magnesium.1-2

When it comes to magnesium intake, the Recommended Dietary Allowance (RDA) for magnesium ranges from 310-400 mg/day in adult women and 400-420 mg/day in adult men. The tolerable upper intake level (UL) for magnesium supplements is set at 350 mg/day for all adults.1,2

Note: RDA refers to the average daily dietary intake from all sources (food and supplements) needed to meet the requirements of healthy individuals in a specific life stage. UL means the highest level of daily intake unlikely to have a risk of adverse health effects.

In general, adverse health effects are unlikely to occur from eating foods that naturally contain magnesium, and diarrhea is the first symptom an individual is likely to experience from taking too much supplemental magnesium. Certain groups of people, such as individuals with decreased kidney function, have a higher risk of magnesium toxicity. In general, for all populations, magnesium supplementation above the set UL is only recommended under medical supervision.2

Can you take magnesium while pregnant?

When it comes to dietary intake of magnesium during pregnancy, the RDA of magnesium during pregnancy is frequently not met. The average intake of magnesium from food (not supplements) for women of childbearing age is about 22% less than the RDA recommendations. Keep in mind the RDA for magnesium during pregnancy is 400 mg/day in individuals 18 years and younger, 350 mg/day for ages 19-30, and 360 mg/day for those 31 and up.1,3 

If you are wondering, “Is magnesium safe during pregnancy?”, for those who are healthy, how much magnesium you can take while pregnant remains at or below the UL unless under medical supervision. A recent analysis of published research suggests the recommended UL for pregnancy may benefit from being updated; however, at this time it remains at 350 mg/day.3 Supplementation with higher doses should only be used under the care of a health-care practitioner.

Keep in mind that magnesium supplements during pregnancy include supplementation from all non-food sources. Be sure to check the label of your prenatal multivitamin and any other supplements and/or medications you are taking, then add the amount of magnesium in each to determine your total daily supplemental intake. 

Along with prenatal multivitamin/multimineral supplements, certain medications such as antacids and laxatives often contain magnesium. So, be sure to check the label on everything you are taking.

Can you take magnesium citrate while pregnant?

Many magnesium supplements contain magnesium citrate. Pregnancy is a time when you might be particularly interested in choosing well-absorbed and concentrated forms of vitamins and minerals. Magnesium citrate has a higher mineral concentration than some other forms of magnesium. For example, magnesium citrate contains 16% magnesium while magnesium bisglycinate contains 8%. And while both forms are well-absorbed, magnesium bisglycinate is recognized as a form with superior absorption.

Your next question might be, “Can you take magnesium glycinate while pregnant?” The answer remains the same as for magnesium citrate. Pregnancy supplementation includes the total amount of magnesium in all supplements you are taking, so be sure to include all forms of magnesium whether you’re taking glycinate, citrate, malate, or other common, less well-absorbed forms, such as magnesium oxide or magnesium sulfate. 

Thorne’s Basic Prenatal multivitamin/mineral contains 90 mg of magnesium per three-capsule serving – 45 mg as magnesium citrate and 45 mg as magnesium malate. For those who need additional magnesium supplementation to help bridge dietary gaps, Magnesium CitraMate is an encapsulated option with 55 mg of magnesium citrate and 80 mg of dimagnesium malate per capsule. Magnesium Bisglycinate contains 200 mg per scoop with a lightly sweet, citrus taste.

Now that we have answered many of your FAQs – including “Can you take magnesium citrate while pregnant?” and “Can you take magnesium glycinate while pregnant?” – we hope you will take the time to check all of your supplements for magnesium content. Talk with your health-care practitioner to determine which magnesium supplement might be right for you during different life stages, and if you need help locating a health-care practitioner who understands your unique supplemental needs, be sure to check out our Find a Professional resource.

References

  1. National Institutes of Health. Magnesium. National Institutes of Health. Published June 2, 2022. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/ [Accessed February 5, 2025]
  2. Magnesium. Linus Pauling Institute. Published April 23, 2014. https://lpi.oregonstate.edu/mic/minerals/magnesium#food-sources [Accessed February 5, 2025]
  3. Adams JB, Sorenson JC, Pollard EL, et al. Evidence-based recommendations for an optimal prenatal supplement for women in the U.S., Part two: Minerals. Nutrients. 2021;13(6):1849.