The 8 Best Magnesium Supplements, According to Dietitians

• Best overall: Life Extension Magnesium Caps
• Best magnesium powder: Thorne Magnesium Bisglycinate Powder
• Best for anxiety: Klaire Labs Magnesium Glycinate Complex
• Best for leg cramps: MegaFood Magnesium
• Best for migraine: Douglas Laboratories Magnesium Oxide
• Best for magnesium deficiencies: Trace Minerals Mega-Mag
• Best for constipation: Pure Encapsulations Magnesium Citrate, Pure Encapsulations Magnesium Liquid

When shopping for a magnesium supplement, it’s important to consider the form of magnesium, dosage, and product quality.

Form of magnesium

First, you’ll want to choose the form of magnesium that’s most appropriate for your needs.

Magnesium comes in the following forms:

• magnesium glycinate
• magnesium citrate
• magnesium chloride
• magnesium sulfate
• magnesium oxide
• magnesium malate

These forms differ in terms of their absorbability and specific uses. For example, magnesium citrate and glycinate have been shown to be absorbed better than magnesium oxide and sulfate, though the research on the absorption is mixed (4, 5).

Additionally, certain types are more beneficial for treating symptoms such as constipation and headaches. That’s why it’s important to choose high quality supplements that come in the form that’s most likely to help with your specific needs (6).

Appropriate dosage

The recommended dose for magnesium supplements varies depending on the brand, the intended use, and how much of this mineral you’re already getting in your diet (1).

Here are the current average daily recommended amounts of magnesium for teens and adults (7):

To avoid potential side effects, such as diarrhea, nausea, and stomach cramps, try to keep your intake of magnesium from supplements under 350 mg per day, unless a healthcare professional has advised you otherwise (7).

Supplement quality

Given that the Food and Drug Administration (FDA) doesn’t regulate supplements the same way as drugs, it’s important to look for brands that are certified by a third-party organization such as NSF International, Labdoor, UL Solutions, or USP. This will help ensure quality and accuracy.

it’s also worth choosing products from brands that are current good manufacturing practices (CGMP) certified. This means that their facilities are compliant with current good manufacturing practice regulations established by the FDA.

Finally, consider avoiding products with any artificial ingredients, such as colors, flavors, and preservatives.

Healthline evaluated the best magnesium supplements based on the following criteria:

• Ingredients: We looked for products that are made from high quality ingredients and free from artificial colors and preservatives.
• Intended use: We included products made to address specific needs such as migraine, constipation, leg cramps, and sleep problems.
• Type of magnesium: The supplements on our list contain forms of magnesium that have been shown to be effective for each product’s intended use.
• Vetting: All the products included have been vetted to ensure that they meet Healthline’s medical and business standards.

Best overall magnesium supplement

Life Extension Magnesium Caps

• Price: $
• Age range: adult
• Type: capsules
• Form of magnesium: oxide, citrate, succinate
• Dose: 1 capsule per day
• Magnesium per serving: 500 mg (119% of the Daily Value [DV])
• Who it’s best for: people who have inadequate magnesium intake and are looking for a magnesium supplement to support whole body health

Life Extension is a trusted company that has been making high quality supplements for more than 40 years.

The company prides itself on transparency and quality, and each of its products is manufactured in an NSF-registered CGMP facility and contains a certificate of analysis (COA) that allows you to confirm its quality and accuracy.

In addition to being rigorously tested for quality and accuracy, Life Extension’s Magnesium Caps are the most budget-friendly option on our list.

The capsules are non-GMO verified and combine magnesium oxide, citrate, succinate, and chelated glycinate.

Just keep in mind that these pills pack more than 100% of the DV for magnesium, so it’s best to check with a healthcare professional before taking this higher dose.

Best magnesium powder

Thorne Magnesium Bisglycinate Powder

• Price: $$$
• Age range: adult
• Type: powder
• Form of magnesium: bisglycinate chelate
• Dose: 1 scoop (3.95 grams) per day
• Magnesium per serving: 200 mg (48% of the DV)
• Who it’s best for: competitive athletes or those who dislike swallowing pills

Thorne Research is known for creating high quality supplements that have been extensively researched.

Its products are made in a lab that meets quality and safety standards set by NSF International and the Therapeutic Goods Administration (TGA), a regulatory body in Australia responsible for assessing supplements.

Thorne Research supplements are also NSF Certified for Sport, which ensures that they’re free from more than 200 substances banned by many major sports organizations.

Thorne Magnesium Bisglycinate Powder is one of the best magnesium powders on the market because of its high quality and limited ingredient list.

Unlike other magnesium powders, it’s flavored only with monk fruit concentrate and is free from added sugars, thickeners, and artificial flavors and colors. Plus, it gets good reviews for its flavor and ease of use.

Best magnesium supplement for anxiety

Klaire Labs Magnesium Glycinate Complex

• Price: $
• Age range: adult
• Type: capsule
• Form of magnesium: bisglycinate chelate, oxide
• Dose: 1 capsule, 1–3 times per day
• Magnesium per serving: 100 mg (24% of the DV)
• Who it’s best for: people with anxiety

In addition to aiding sleep, magnesium’s calming effect on the nervous system may alleviate anxiety.

While more research is needed, a review of 18 human studies suggests that magnesium may reduce anxiety symptoms (8).

Klaire Labs Magnesium Glycinate Complex is one of the best options. It’s third-party tested, manufactured in a CGMP-certified facility, and free from artificial colors, flavors, and preservatives.

Each capsule blends chelated magnesium glycinate with magnesium oxide.

While magnesium glycinate is commonly used to help with sleep and anxiety, magnesium oxide is one of the most common forms tested in studies examining anxiety (8).

For best results, it’s recommended to take a single capsule 1–3 times per day, or as directed by a healthcare professional.

Best magnesium supplement for leg cramps

MegaFood Magnesium

• Price: $$
• Age range: adult
• Type: tablet
• Form of magnesium: fermented bisglycinate
• Dose: 1 tablet per day
• Magnesium per serving: 50 mg (12% of the DV)
• Who it’s best for: people with regular muscle cramps

Magnesium has been shown to act as a natural calcium blocker to help your muscles relax. That’s why insufficient magnesium intake is thought to cause some muscle cramps (9).

While the research is inconclusive, some individuals report muscle cramp relief from taking magnesium (10, 11).

If you’re curious whether magnesium can help relieve your nighttime leg cramps, you may want to check out MegaFood Magnesium.

MegaFood is a Certified B Corporation — a legal designation verified by B Lab, a nonprofit organization. The designation is given to companies that meet rigorous standards for accountability, transparency, and social and environmental performance.

MegaFood’s Magnesium supplement is tested for more than 125 pesticides and herbicides, as well as quality-verified and certified non-GMO, vegan, and gluten-free.

In addition to magnesium, each tablet contains 50 mg of organic spinach, which is a good source of magnesium (12).

MegaFood’s Magnesium is praised for its ability to reduce leg cramps. Unlike many other supplements, it can be taken on an empty stomach. As a result, you can easily take it just before bed to help keep nighttime cramps at bay.

Best magnesium supplement for migraine

Douglas Laboratories Magnesium Oxide

• Price: $
• Age range: adult
• Type: capsules
• Form of magnesium: oxide
• Dose: 1 capsule per day
• Magnesium per serving: 300 mg (75% of the DV)
• Who it’s best for: people with recurring migraine headaches

Migraine attacks are debilitating headaches often associated with symptoms like nausea, weakness, and sensitivity to light and sound (13).

Human research indicates that magnesium supplements may help prevent and manage migraine attacks (14, 15).

Magnesium oxide is one form of magnesium that’s thought to be effective for migraine, though more research is needed.

Still, if you’re looking for a way to help manage recurring migraine headaches, it’s worth considering Douglas Laboratories Magnesium Oxide (15, 16).

Douglas Laboratories makes all its products in an NSF-registered GMP facility. Its supplements are also non-GMO verified.

It’s worth noting that some reviewers mention diarrhea as a side effect of the supplement.

Best for magnesium deficiencies

Trace Minerals Mega Mag

• Price: $$
• Age range: adult
• Type: liquid
• Form of magnesium: chloride
• Dose: 1–4 mL (1–4 droppers) per day
• Magnesium per serving: 400 mg (95% of the DV)
• Who it’s best for: people diagnosed with a magnesium deficiency

If you’ve been diagnosed with a magnesium deficiency, Trace Mineral Mega Mag is worth considering.

The liquid supplement provides 95% of the DV of magnesium in the form of magnesium chloride — a form that’s often used to address low blood levels of magnesium.

This supplement comes in a convenient liquid form and is free from artificial ingredients and added sugars. The only ingredients are magnesium, chloride, sodium, potassium, sulfate, and boron.

Trace Minerals supplements are third-party tested by Labdoor and manufactured in a CGMP-registered facility.

The taste of this product can be strong, so it’s recommended to mix the liquid with water, juice, or food.

Best magnesium supplements for constipation

Magnesium supplements are thought to be an effective treatment for occasional constipation (17, 18).

In particular, magnesium citrate, sulfite, hydroxide, and oxide all have an osmotic laxative effect (17, 18).

This means that these supplements help relax your bowels and draw water into your intestines to soften stool and make it easier to pass.

However, there’s limited research on the effectiveness of magnesium citrate, sulfite, and hydroxide in the management of chronic constipation (17).

When taking magnesium for constipation, you should consult a healthcare professional for individualized dosage recommendations.

Pure Encapsulations Magnesium Citrate

• Price: $
• Age range: adult
• Type: capsules
• Form of magnesium: citrate
• Dose: 1 capsule, 1–4 times per day
• Magnesium per serving: 150 mg (36% of the DV)
• Who it’s best for: people with constipation

If you’re experiencing constipation, Pure Encapsulations Magnesium Citrate is a high quality option.

Made in a facility that’s NSF-registered and CGMP-certified, this supplement is also vegan, non-GMO verified, and certified gluten-free by the Gluten-Free Certification Organization.

This middle-of-the-road dose of magnesium citrate can help move things along without causing an urgent trip to the bathroom.

For best results, take a single pill with a meal, 1–4 times a day, depending on recommendations from a healthcare professional.

Pure Encapsulations Magnesium Liquid

• Price: $$$
• Age range: adult
• Type: liquid
• Form of magnesium: citrate
• Dose: 1 teaspoon (5 mL)
• Total magnesium: 215 mg (51% of the DV)
• Who it’s best for: people with constipation who prefer a liquid supplement

For those who prefer a liquid supplement, Pure Encapsulations also offers liquid magnesium citrate.

Free from artificial sweeteners and colors, this product contains natural fruit flavors, apple juice concentrate, and stevia extract to make it more palatable.

Pure Encapsulations Magnesium Liquid is certified gluten-free and verified non-GMO.

For best results, it’s recommended to consume 1 teaspoon (5 mL) with a meal once per day, or as directed by a healthcare professional.

Keep in mind that this supplement also contains a high amount of vitamin B6. Therefore, it should not be taken along with a multivitamin or other supplement containing vitamin B6.

Here’s a quick look at how our top picks compare:

What is the most effective form of magnesium to take as a supplement?

The best form of magnesium to take depends on the desired benefit.

For example, research indicates that magnesium citrate is the most effective form for treating constipation, whereas magnesium oxide may be better suited for those experiencing anxiety or migraine (15, 16, 17).

For this reason, it’s important to choose a supplement that includes magnesium in the form that’s most effective for your specific needs (6).

Should I take magnesium supplements?

People who have a magnesium deficiency or have trouble getting enough magnesium in their diet should consider taking a magnesium supplement (7).

However, before beginning any new supplement, you should talk it over with a healthcare professional, especially if you are taking any medications or are pregnant or nursing.

Specifically, magnesium supplements may be unsafe for individuals who are taking diuretics, heart medications, or antibiotics (19).

What are magnesium supplements good for?

Magnesium supplements may provide several health benefits, including lowering blood pressure, reducing the risk of heart disease, and improving sleep (20, 21, 22).

Additionally, magnesium supplements may help relieve anxiety, muscle cramps, and constipation, though more research is needed (1, 3).

How much magnesium is safe to take?

The total recommended daily intake of magnesium is 400–420 mg for men and 320–360 mg for women. Keep in mind that this number includes all magnesium, from both food sources and supplements (19).

The upper limit for magnesium from supplements specifically is 350 mg (19).

We recommend speaking with a healthcare professional about an appropriate dosage for you.

Are there side effects of taking magnesium supplements?

Magnesium supplements can cause some digestive issues, including nausea, stomach cramping, and diarrhea, especially when taken at higher doses (19).

Additionally, certain individuals, such as those with kidney conditions, can be more susceptible to side effects (23).

Magnesium is an essential nutrient found in a variety of foods, including whole grains, beans, nuts, and leafy green vegetables.

Supplements are a good option for people who don’t meet their needs through diet alone.

Because the FDA doesn’t regulate supplements the same way that it regulates medications, it’s important to choose reputable brands that have undergone quality testing. To make your decision simpler, you can select a product from the list above.

If you’re unsure how much to take or which type is most appropriate for your needs, speak with a healthcare professional for a specific recommendation.