Magnesium helps with common pregnancy side effects like muscle cramps and nausea, and helps to regulate things like your blood sugar and blood pressure. See how it effects your pregnancy and FAQs.
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Table of Contents
What is Magnesium & What Does it Do?
Magnesium is a mineral involved in over 300 chemical reactions in the body. You need magnesium to help with nerve and muscle function, immunity, healthy blood pressure, blood sugar, calcium absorption, heart rhythm and tons more. (1)
What Does Magnesium Do in Pregnancy?
Magnesium contributes to bone development and DNA formation (things the baby needs), as well as healthy blood pressure and regulating blood sugar (fighting preeclampisa, gestational diabetes, and other complications associated with high blood pressure and high blood sugar in pregnancy).
Magnesium deficiency in pregnancy effects both mom and baby. It is linked to preterm births, low birth weight, high blood pressure and preeclampsia. (2)
Sufficient magnesium intake in pregnancy is linked to optimum growth for baby. (2)
If you didn't know, blood sugar control is a big concern in EVERY pregnancy, even if you're never diagnosed with gestational diabetes.
Studies show that higher blood sugars correlate with increased complications, even though the mother did not have blood sugars high enough to be diagnosed with gestational diabetes. (3)
Increased magnesium, whether through natural intake or supplementation, is proven to improve blood glucose levels. (4)
In Facebook groups, moms have said their doctor gave them a magnesium supplement to help with muscle cramps and other things, and as an added benefit, their blood sugars improved.
Recommended Daily Intake
The FDA recommends 400mg of magnesium per day to prevent severe deficiency. Updated and independent research recommends 482mg of magnesium each day. (5)
If you're interested in other nutrient recommendations, see this chart for recommended daily intakes for nutrients in pregnancy.
How to Know if You Need More Magnesium
Your body has the amazing ability to correct and heal itself naturally. Magnesium regulation is proof of that.
Your kidneys help regulate the magnesium in your body by excreting it through your urine. So whether you're getting a little or a lot of magnesium, your kidneys monitor your levels and either hold on to the magnesium if you need it, or push it out in your urine if you have too much. (1)
But, there's always an exception.
If you habitually have a low intake of magnesium, which is likely in the North American diet, or if other health conditions cause you to excrete more than you should, you can be deficient. (1)
Type 2 diabetics, people with a gastrointestinal disease, people who are older, or those who are heavy drinkers are likely to be deficient. (1)
Magnesium Deficiency in Pregnancy
Because the average North American diet isn't rich in magnesium, there's a 50% chance you're deficient; pregnant or not. (6)
Though the beginning symptoms of magnesium deficiency are common to side effects in pregnancy (nausea, vomiting, etc.), a stand out sign is muscle cramps.
The good news is that your levels are checked when your doctor orders your blood work. So if you're deficient, you'll likely know when your blood work is finished.
Symptoms of Magnesium Deficiency
Early signs of low magnesium intake include loss of appetite, nausea, vomiting, fatigue, and weakness - all of which are super common in pregnancy.
As "deficiency worsens, numbness, tingling, muscle contractions and cramps, seizures...abnormal heart rhythms" and more can occur.
The Best Sources for Magnesium
The best food sources for magnesium include, dark leafy greens (namely, spinach), nuts (namely, almonds, cashew, and peanuts), seeds, avocados, and cocoa, all of which are low carb. (1)
Beans, whole grains, and magnesium-fortified foods are good sources, but they are higher carb, so you may want to eat less of these (or smaller portions) while pregnant for consideration of your blood sugars.
Non food sources of magnesium include supplements, magnesium sprays for your skin, and Epsom salt (for baths and soaks).
Before seeking a magnesium supplement, look at the dosage in your prenatal vitamin and talk to your doctor. Magnesium supplements sometimes interfere with medications and other conditions in your body that may take priority. (1)
There are different forms of magnesium.
Magnesium aspartate, magnesium citrate, magnesium lactate, magnesium chloride, and magnesium glycinate are the best absorbed forms. (1, 6)
Magnesium glycinate is least likely to cause gastrointestinal side effects, but magnesium citrate may be better if you're constipated. (6) Check with your doctor for a recommendation.
Too Much Magnesium
Taking a supplement, in most cases, means that you're getting a high dosage all at once; higher than you would if you ate a meal full of magnesium rich foods.
In a normal diet, your kidneys would excrete the excess magnesium in your urine, but excess magnesium from taking a supplement commonly results in diarrhea. Because of this, limit a magnesium supplement to 350mg a day (1), but start at 100mg so your body can adjust. (6)
Magnesium assists in over 300 bodily functions to include DNA formation, bone building, heart rhythm, and blood pressure and blood sugar regulation.
Beginning symptoms of low magnesium are loss of appetite, nausea, vomiting, fatigue, and weakness.
Next level symptoms are muscle cramps, numbness, tingling, abnormal heart rhythms, and seizures.
The FDA recommends a daily intake (RDI) of 400mg. Updated and independent research recommends a RDI of 482mg.
Nuts, seeds, beans, dark leafy greens, and whole grains naturally have moderate to high magnesium depending on the serving size. Other options are magnesium-fortified foods.
You can absorb magnesium through your skin with Epsom salt baths or foot soaks, or topical magnesium sprays and lotions. (5)
Getting magnesium through food is best, but supplementation is sometimes necessary. It's safe to supplement magnesium in pregnancy, but you should consult your doctor first and have your blood work checked.
Magnesium aspartate, magnesium citrate, magnesium lactate, magnesium chloride, and magnesium glycinate are the best absorbed forms. Magnesium glycinate is least likely to cause gastrointestinal side effects, but magnesium citrate may be better if you're constipated. Check with your doctor for a recommendation.
Magnesium helps your body perform many tasks: important to pregnancy are DNA formation, bone building, heart rhythm, blood pressure, blood sugar regulation, nerve and muscle function, and more.
You have to get magnesium through food, supplementation, or skin absorption.
The common North American diet is not rich in magnesium, so there's about a 50% chance that you're deficient. Since beginning symptoms of deficiency are also common side effects of pregnancy, check your blood work to know for sure if you're deficient.
People with certain preexisting conditions, who are older, or who are heavy drinkers are more likely to be deficient. Pregnant American women, namely those with gestational diabetes, are commonly deficient.
The best sources for magnesium are dark leafy greens, avocado, cocoa, nuts, and seeds. Other sources are beans, whole grains, Epsom salt, sprays, lotions and supplements.
1. Magnesium Facts
2. Effects in Pregnancy
3. Hyperglycemia and Adverse Pregnancy Outcomes
4. Glucose Control with Supplementation
5. Recommended Daily Intake (RDI) for Magnesium
6. Real Food for Pregnancy
7. Magnesium Forms