Magnesium: The Mighty Mineral

Thanks to a variety of health influencers touting its benefits on social media, magnesium is currently the second most popular supplement, right after Vitamin D and just before Omega 3. As with all supplements, this raises some questions. Who needs magnesium supplements and if so, what type, and what dose? Most importantly, what does your doctor think? While magnesium toxicity is rare, overuse can cause diarrhea, nausea, and stomach cramps.

Magnesium deficiency is not uncommon, especially in athletes and people with diabetes or illnesses that affect intestinal absorption, such as Crohn’s or IBS. Excess alcohol consumption and overuse of calcium supplements can also lead to magnesium deficiency. There are many types of magnesium, and you want to make sure you take the right kind, brand and dose. Supplements are not vetted by the FDA, but you can learn more about a product on the NIH’s Dietary Supplement Label Database.

Types of Magnesium

Magnesium is the fourth most common element on Earth, making up 13% of the planet's mass, and the third most abundant element dissolved in seawater, after sodium and chlorine. Because it is highly reactive, magnesium easily combines with other substances. The types of magnesium listed below are named for the element or amino acid the magnesium is bound with. For example, magnesium oxide is a combination of magnesium and oxygen.

• Magnesium Citrate, a magnesium salt of citric acid, is easily absorbed by the digestive tract, making it one of the most popular magnesium supplements. In addition to being used for overall magnesium deficiency, it helps relieve constipation and muscle cramps.
• Magnesium Glycinate is bound to the amino acid glycine. It is easily absorbed and gentle on the stomach, and often recommended to induce muscle relaxation and help with stress or sleep issues.
• Magnesium Oxide, a combination of magnesium and oxygen, is less well-absorbed by the digestive system. Because of this, it is not recommended for magnesium deficiency. However, it is sometimes used to treat digestive issues and constipation.
• Magnesium Malate is combined with a compound found in many fruits called malic acid. Relatively easily absorbed, it is used to boost energy and treat muscle pain and sometimes prescribed as a supplement for people with fibromyalgia or chronic fatigue syndrome.
• Magnesium Taurate, which is combined with the amino acid taurine, is well absorbed and beneficial for cardiovascular health, anxiety, and stress.
• Magnesium Threonate is believed to cross the blood-brain barrier. It is used for cognitive support, focus, memory, and mental clarity. There is ongoing research into its use to slow age-related cognitive decline.
• Magnesium Chloride, a salt of magnesium and hydrochloric acid, is easily absorbed orally and through the skin. It is a common ingredient in bath salts and creams used to soothe muscle pain, cramps, and skin irritations.
• Magnesium Sulfate is commonly known as Epsom salt. It dissolves easily in water and is mostly used for bathing to treat muscle soreness and promote relaxation. It is also used intravenously to treat eclampsia or magnesium deficiency.
• Magnesium Carbonate is not as easy to absorb as other magnesium compounds and must be broken down in the stomach. It is a common ingredient in antacids such as Gaviscon and Pepto Bismol.
• Magnesium Aspartate, which is combined with the amino acid aspartic acid, is not as commonly used as a supplement as other forms of magnesium. It can be used as a mild energy booster.

Getting Your Magnesium from Food

It’s usually best to get your nutrients, minerals, and vitamins from a healthy diet. These foods are rich in magnesium:

• Whole grains, such as brown rice, barley, spelt, or quinoa
• Dark, leafy greens such as spinach, kale, arugula, collards, or char
• Nuts, especially almonds, cashews, and peanuts
• Seeds, such as pumpkin or chia
• Beans, such as black, kidney, or cannellini
• Legumes such as peas, chickpeas, lentils, or edamame
• Fruits, especially avocado and banana
• Fortified breakfast cereals and oatmeal
• Milk (cow or soy) and milk products such as yogurt
• Dark chocolate
• Raisins and prunes
• Potatoes with the skin on
• Salmon
• Tofu

If you are interested in trying a magnesium supplement, be sure to talk to your doctor first. He or she can help you determine which one is best for you and at what dose. To find a doctor, click Find a Provider.

This article first appeared in the January 2025 edition of the HealthPerks newsletter.