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Could you see health benefits from adding a magnesium supplement to your routine? Or is it the latest hyped-up supplement that you really don’t need?
People take magnesium supplements to reduce migraines, constipation, muscle cramps, restless leg syndrome, nausea, and to improve muscle recovery and sleep.
Before reviewing the evidence-based health benefits, let’s look at magnesium’s role in the body.
What Is Magnesium and Where Can I Find It?
Magnesium is a mineral that has many roles in the body. It helps with the body systems that control muscles, nerves, energy, bone health, blood pressure, and blood sugar levels.
The mineral is found in many foods and in some medications, most notably for constipation and heartburn.
The foods with the most magnesium are:
- nuts (almonds, cashews, peanuts); spinach and other green leafy vegetables
- legumes (black beans, soy foods including edamame and soymilk)
- grains (wheat, brown rice); fruits (avocado, bananas)
- hard tap water and bottled mineral waters
What are the Main Health Benefits of Magnesium?
It makes sense that taking a magnesium supplement could allow your blood vessels to expand, speed up your nerve signals, and relieve migraine pain.
A side effect of large doses of magnesium is diarrhea. This is the reason it is in laxatives. It is effective if you are having difficulty going to the bathroom.
Over the counter laxatives that contain magnesium would be a better choice than a magnesium supplement.
High levels of magnesium in the blood appear to reduce the risk of cardiovascular disease and stroke. Major limitation of these studies, however, is that magnesium status and intake are measured in different ways and other dietary patterns are not always considered. This makes it difficult to draw any firm conclusions.
It is important for blood glucose management. Low levels of magnesium make it more difficult for your body to manage the sugars from the foods you eat. Over time, this may lead to insulin resistance or diabetes.
It is important for building and maintaining strong bones. Magnesium may improve bone mineral density. Low levels of magnesium may increase your risk for osteoporosis.
Do I Have Magnesium Deficiency?
Even if you think you may not be eating enough foods with magnesium, having a magnesium deficiency is rare. Your kidneys hold onto magnesium when your body needs it.
Deficiency is more likely if you have type 2 diabetes, drink alcohol regularly, have gastrointestinal (GI) diseases such as celiac disease or Crohns’ disease, have had GI surgery, and are an older adult.
Signs of a deficiency are feeling nauseous, vomiting, losing your appetite, or feeling tired and weak. A more severe deficiency may make you feel numb, give you muscle cramps or a tingling sensation, and result in heart palpitations.
How Should I Take Magnesium Supplements?
Supplementation may be a way to correct a magnesium deficiency. Much of the research indicates that correcting a deficiency can improve symptoms. However, just taking more magnesium if you do not have a deficiency may not be a wise decision.
There is also a Tolerable Upper Limit for magnesium supplements, which is the maximum amount you should take. Healthy adults over 19 should not take more than 350 milligrams of magnesium in supplement form. There is no upper limit for magnesium that comes from food sources.
This upper limit is more important if you have kidney issues, as healthy kidneys do a good job of getting rid of excess magnesium. Side effects from too much magnesium include diarrhea, a severe drop in blood pressure, confusion, heart rhythm issues, loss of kidney function, muscle weakness, and difficulty breathing.
At the extreme, cardiac arrest is possible. Magnesium supplements may interfere with certain medications including heart medications, blood thinners, diuretics, antibiotics, and osteoporosis drugs.
The Average American eats 235 -350 milligrams of magnesium a day from foods. However, your body can only take in and use about 35%. This means many people maybe not be getting enough magnesium from food.
Magnesium may come from food, multi-vitamins, or dietary supplements. Magnesium supplements come in many different forms.
You should talk to your medical provider about the best form for you to use and any medication or health concerns before you begin taking a magnesium supplement.
Health Insiders relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.
 U.S. Department of Health and Human Services. National Institutes of Health. Office of Dietary Supplements. Magnesium: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional. Accessed December 10, 2019.
 U.S. National Library of Medicine. Medline Plus. Magnesium in Diet. https://medlineplus.gov/ency/article/002423.htm. Accessed December 10, 2019.
 Oregon State University. Linus Pauling Institute. Micronutrient Information Center. Magnesium. https://lpi.oregonstate.edu/mic/minerals/magnesium. Accessed December 11. 2019.