All About Magnesium Supplementation
Physical Health
Magnesium supplements can be marketed for a wide variety of health claims. From boosting your mood, to preventing migraines, to lowering blood pressure. But can a magnesium supplement really do all of it?
In this article, we’ll talk about what magnesium does for your body and what research says about the benefits of magnesium supplements.
What Is Magnesium?
Magnesium is a mineral that you need to stay healthy. You need magnesium for several functions in your body, including:
- Making proteins
- Helping your muscles and nerves work properly
- Controlling your blood sugar
- Regulating your blood pressure
- Making new bone tissue
- Regulating your heart rhythm
What Are Natural Sources of Magnesium?
You can find magnesium in several plant-based and animal-based foods. Examples of magnesium-rich foods include:
- Nuts and seeds — such as almonds, cashews, and pumpkin seeds
- Legumes — such as black beans, kidney beans, and edamame
- Whole grains — such as quinoa, oatmeal, and brown rice
- Dairy products — such as milk and yogurt
- Leafy greens — such as spinach and collard greens
- Vegetables — such as peas, corn, and potatoes
- Fruit — such as avocados, bananas, and papaya
- Dark chocolate
- Tap or mineral water
How Much Magnesium Do You Need?
The amount of magnesium you need every day depends on your age and sex. The recommended daily allowance (RDA) for magnesium is the average amount of magnesium that most healthy people need. You can find the recommended daily allowance (RDA) for magnesium in Table 1.
Table 1. RDA of Magnesium Based on Life Stage
| Life Stage | Recommended Amount of Magnesium (in mg) |
|---|---|
| Birth to 6 months | 30 mg |
| Infants 7 months to 12 months | 75 mg |
| Children 1 to 3 years | 80 mg |
| Children 4 to 8 years | 130 mg |
| Children 9 to 13 years | 240 mg |
| Adolescent boys 14 to 18 years | 410 mg |
| Adolescent girls 14 to 18 years | 360 mg |
| Adult men | 400 to 420 mg |
| Adult women | 310 to 320 mg |
| Pregnant women | 350 to 360 mg |
| Breastfeeding women | 310 to 320 mg |
The magnesium amounts listed in Table 1 are recommended for healthy people. You may have different requirements based on your specific needs and health conditions. Talk to your health care provider about the amount of daily magnesium recommended for you based on your age, sex, and health conditions.
Types of Magnesium Supplements
You can find magnesium supplements in several different forms, such as capsules, tablets, and powders. There are also different types of magnesium compounds used in supplements, including:
- Magnesium citrate
- Magnesium gluconate
- Magnesium lactate
- Magnesium aspartate
- Magnesium oxide
- Magnesium chloride
- Magnesium glycinate
Magnesium hydroxide (Phillips’ Milk of Magnesia) is another type of magnesium that’s used to treat constipation, heartburn, or upset stomach. It usually isn’t used as a magnesium supplement because it can cause diarrhea. However, taking this medication will count towards your total daily dose of magnesium.
Different types of magnesium supplements can differ in how fast they’re absorbed and to which parts of the body they’re distributed. Some studies have found that your body may absorb more magnesium in the form of aspartate, citrate, lactate, and chloride compared to magnesium oxide or sulfate. Talk to your health care provider to learn more about which magnesium supplement is best for you.
What Are the Evidence-Based Benefits of Magnesium Supplements?
Magnesium supplements are one way to make sure you’re getting enough magnesium to stay healthy. Researchers have investigated the effect of magnesium supplements in several health conditions.
High Blood Pressure
A magnesium supplement may help lower blood pressure to a small extent. However, the studies that have been done to date are of low quality, and the results may be due to bias. A magnesium-rich diet is associated with lower blood pressure. However, this may be due to the fact that a magnesium-rich diet is also rich in other vitamins and minerals.
Heart Disease and Stroke
Higher levels of magnesium in your blood may help prevent certain types of heart disease, including sudden cardiac (heart) death and ischemic heart disease (heart problems caused by poor blood flow to your heart). Higher dietary magnesium intake is also associated with a reduced risk of having a stroke (a condition caused by poor blood flow to your brain).
Type 2 Diabetes
Type 2 diabetes is a health condition that causes high blood sugar.
Researchers began investigating the effect of dietary magnesium and magnesium supplements because magnesium plays an important role in managing blood sugar levels. Low magnesium levels may make it harder for your body to regulate blood sugar. Additionally, other health conditions associated with diabetes can cause low magnesium.
Several studies have found that high dietary magnesium intake may reduce the risk of developing diabetes.
A few small clinical trials have looked at the effect of magnesium supplements on blood sugar control in people with type 2 diabetes. In a 1998 study of 128 people with type 2 diabetes, researchers found that taking a magnesium supplement for 30 days helped increase magnesium levels and improve blood sugar control. A 2003 study found that magnesium supplements help to improve fasting blood sugar levels.
Although some studies show promise in using magnesium supplements to help manage diabetes, other studies have conflicting results, showing no improvement. The American Diabetes Association says there isn’t enough evidence to support recommending magnesium supplements for people with diabetes who don’t have low levels of magnesium.
Osteoporosis
Osteoporosis is a condition that causes weak bones that are more likely to break. Magnesium helps to regulate hormones that affect bone formation. Women with osteoporosis are more likely to have low levels of magnesium. Several studies have found an association between higher dietary magnesium intake and higher bone density, which can prevent osteoporosis.
A few small studies have found that magnesium supplements may help increase bone density in older women. However, more research is needed to find out how magnesium supplements may help prevent or treat osteoporosis.
Migraine Headaches
A migraine headache is a type of headache that can be severe and interferes with the ability to participate in daily activities. Research has found that people with migraines have lower levels of magnesium compared to people without migraines. Magnesium is involved in processes related to the development of migraines, such as vasoconstriction (narrowing of blood vessels) and the release of neurotransmitters (chemicals that help your nerves and brain communicate).
There are a few small studies that show magnesium supplements may help prevent migraine headaches. Although there is limited evidence, health experts from the American Academy of Neurology and the American Headache Society have said magnesium is probably effective for migraine prevention.
Asthma
Asthma is a condition that makes it hard to breathe due to airway constriction. Low magnesium levels are linked to an increased risk of developing asthma. Magnesium is involved in relaxing the muscles that can become constricted in the airway in people with asthma. People in the hospital for an asthma attack may get magnesium given through their veins if other treatments don’t work. However, a 2019 review of several studies found that magnesium supplements didn’t significantly improve asthma symptoms.
Restless Legs Syndrome
Restless legs syndrome (RLS) is a condition that causes a strong urge to move your body while resting. A small study found that magnesium supplements may improve insomnia related to RLS.
Other Conditions
Other conditions in which magnesium supplements may be helpful include:
- Depression
- Fibromyalgia
- Hearing loss
- Preeclampsia and eclampsia
- Premenstrual syndrome (PMS)
- Colorectal cancer
How Should You Take a Magnesium Supplement?
The way you take your magnesium supplement depends on what type of magnesium you’re taking. Follow the directions from your health care provider and the directions from the manufacturer.
In the United States (US), the amount of magnesium on the product’s label represents the amount of elemental magnesium in the supplement.
Taking magnesium with vitamin B6 can help increase the amount of magnesium your body absorbs. Some types of magnesium supplements also contain vitamin B6.
Who Needs a Magnesium Supplement?
Many people can get all the magnesium they need from their diet.
In the US, it’s estimated that about half of the population gets enough magnesium from the food and drinks they consume. Even if you don’t get the recommended daily amount of magnesium, your kidneys are good at making sure your body still has the right amount of magnesium. This means that it’s rare for otherwise healthy people to experience symptoms from low magnesium levels.
Symptoms of a magnesium deficiency (low magnesium levels in your blood) include:
- Appetite loss
- Nausea and vomiting
- Fatigue (extreme tiredness)
- Weakness
If you have very low magnesium levels in your blood, it can cause more serious symptoms, such as muscle cramps, seizures, and abnormal heart rhythms. Low magnesium can also affect your blood levels of calcium and potassium.
Some groups of people may be more likely to have low magnesium levels in their blood, such as people with:
- Long-term alcohol use
- Digestive system diseases
- Type 2 diabetes
- Older adults
Certain medications can also cause magnesium deficiency, including diuretics (water pills) and acid reflux medications.
If you have a condition associated with low magnesium levels, talk to your health care provider about whether a magnesium supplement is right for you.
What Are the Risks of Magnesium Supplements?
As with most supplements, there are potential risks. Health experts generally agree that getting too much magnesium from your food isn’t an issue for most people. The magnesium from your diet is easily processed by your kidneys. However, high doses of magnesium from supplements may cause side effects or interact with some medications.
Side Effects
The most commonly reported side effects of magnesium supplements are diarrhea, stomach cramps, and nausea.
Serious health problems associated with very high doses of magnesium include:
- Nausea and vomiting
- Low blood pressure
- Confusion
- Slow heart rate
- Difficulty breathing
- Coma
- Irregular heartbeat
- Heart problems
- Death
Drug Interactions
Magnesium can interact with several different medications. This is why it’s important to talk to your health care provider before you start taking any new medication, vitamin, or supplement. If you’re taking magnesium, make sure your provider knows before they prescribe a new medication. Below is a list of some medications that can interact with magnesium supplements. However, this list may not include every medication with a potential interaction.
Antibiotics
The absorption of some antibiotics is reduced when they’re taken at the same time as magnesium. Your health care provider or pharmacist may recommend taking your antibiotic 2 hours before or 6 hours after taking magnesium. Some antibiotics that can interact with magnesium include:
- Ciprofloxacin (Cipro)
- Levofloxacin (Levaquin)
- Moxifloxacin (Avelox)
- Doxycycline (Vibramycin, Doryx, and other brand names)
- Minocycline (Minocin)
Diabetes Medications
Some types of magnesium supplements may increase the absorption of some medications used to help lower blood sugar in people with diabetes. This can increase the medication’s effect, leading to blood sugar that’s too low. Examples of diabetes medications that may interact with magnesium include glipizide (Glucotrol) and glyburide (Micronase).
Osteoporosis Medications
If you take magnesium with bisphosphonates (a class of medications used to treat and prevent osteoporosis), it can decrease the absorption of bisphosphonates. Your health care provider or pharmacist may recommend separating these medications by at least 2 hours. Alendronate (Fosamax) is an example of a bisphosphonate medication.
Diuretics
Diuretics, also known as water pills, can affect your blood magnesium levels. If you’re taking a diuretic, your health care provider will closely monitor your magnesium level, along with other electrolytes. Examples of diuretic medications include:
- Furosemide (Lasix)
- Bumetanide (Bumex)
- Hydrochlorothiazide (Microzide)
- Spironolactone (Aldactone)
Proton Pump Inhibitors
Proton pump inhibitors (PPIs) are medications used to treat acid reflux (heartburn). Long-term PPI use can lead to low magnesium levels. Your health care provider will closely monitor your magnesium levels while taking this medication. Magnesium supplements may not increase low magnesium caused by PPIs.
Talk to Your Health Care Provider About Magnesium Supplements
Magnesium is an important mineral that helps maintain your health. Magnesium supplements may be helpful for people with or at risk for low magnesium levels. There’s some evidence that magnesium supplements may be helpful for certain medical conditions. It’s important to discuss adding a magnesium supplement to your treatment plan with your health care provider to make sure it will not cause any health issues or interact with your medications.
