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Best magnesium supplement

Which magnesium supplement is best?

Magnesium is an essential mineral that controls numerous functions throughout the body. According to MedlinePlus, it is needed for “more than 300 biochemical reactions in the body.” This includes everything from maintaining healthy blood pressure to keeping bones strong. 

Those who have been diagnosed with a magnesium deficiency are often required to add a supplement to their diet. The Dr. Mercola Magnesium L-Threonate supplement is the premier choice due to its optimum absorption and lack of gastrointestinal effects.

What to know before you buy a magnesium supplement

Size of pill

Quite a few people have difficulty swallowing large pills. If you experience challenges with them, it is important to select a magnesium supplement that's smaller. Even if a supplement is highly rated, don’t order one that you won’t feel comfortable taking. Forcing yourself to swallow a supplement that is too sizable may lead you to skip your recommended dose.

Gastrointestinal effects

Magnesium supplements have a reputation for producing undesirable digestive symptoms. Higher amounts of magnesium act as a natural laxative, which leads to this unpleasant side effect.

This doesn’t have to be the case, though. Some supplements are designed to mitigate all digestive discomfort. This is achieved by using a special kind of magnesium and creating the supplement with high-quality ingredients.


Ultimately, the magnesium supplement you select needs to meet your dosage requirements. This recommendation will vary depending on your body size, the severity of your deficiency and your age.

Rather than selecting a magnesium supplement at random, ensure that your chosen milligrams align with what your doctor has recommended for you. Magnesium pills are often set at lower amounts, which can be increased as needed.

Before starting a magnesium supplement, always consult your doctor, especially if you're taking other medicines. Magnesium can interact with medicines such as blood pressure medication, diuretics and hormone replacement therapy. Never take magnesium without seeking professional advice so you can avoid unpleasant or dangerous side effects.

What to look for in a quality magnesium supplement


Proper absorption is one of the biggest hurdles across all kinds of supplements. Those facing digestive conditions are especially prone to this issue. The ideal magnesium supplement breaks down rapidly so that it can be properly absorbed into the bloodstream. Pills that do not break down quickly enough are passed by the digestive system, and limited-to-no benefits are achieved. 

Pleasant effects

One unusual aspect of magnesium supplements is the immediate benefits experienced. Those who begin taking magnesium often report migraine relief, relaxed muscles and decreased anxiety. Experiencing these effects is a good sign that your magnesium supplement is hard at work.


Quality magnesium supplements should have little to no taste. Unless intentionally flavored like many of the gummy and powdered magnesium supplements on the market, there should be no undesirable aftertaste with this mineral. This is especially the case with gel capsules.

If you desire a specific taste, be sure to look for flavored varieties.

How much you can expect to spend on magnesium supplements

Magnesium supplements cost $5-$40. The price largely depends on factors such as magnesium concentration, number of pills and overall quality.

Magnesium supplement FAQ

Does everyone need to take a magnesium supplement?

A. No. You should only start taking a magnesium supplement if advised to do so by your doctor.

How much magnesium should I take?

A. After performing blood tests, your doctor will be able to provide you with a recommended dosage.

What are some of the benefits of taking magnesium?

A. Magnesium is known for producing a calming and relaxing effect. It can ease headaches and migraines, loosen muscles and reduce feelings of anxiety.

What’s the best magnesium supplement to buy?

Top magnesium supplement

Dr. Mercola Magnesium L-Threonate

What you need to know: This top-quality magnesium supplement is one of the few that promise no unpleasant digestive side effects.

What you’ll love: Because it uses magnesium L-threonate, it doesn't act like a laxative. It's also designed for maximum mineral absorption.

What you should consider: People who have trouble swallowing large pills can sometimes have problems with it.

Where to buy: Sold by iHerb

Top magnesium supplement for the money

Solaray High-Absorption Magnesium Glycinate

What you need to know: This is an affordable, effective supplement made from whole rice concentrate.

What you’ll love: This brand produces exceptional supplements that are an outstanding value. Those who’ve taken Solaray Magnesium report reduced muscle pain and leg cramps, as well as increased relaxation.

What you should consider: Some who have taken this supplement do not enjoy the outer coating of the pill.

Where to buy: Sold by iHerb

Worth checking out

Nature Made Magnesium Citrate

What you need to know: These 250 milligram softegls are budget-friendly and contain no artificial flavors or dyes.

What you’ll love: This gluten-free magnesium supplement is held to the highest quality standards. One bottle provides a 60-day supply for those who take 250 mg per day.

What you should consider: Some reviewers disliked the large size.

Where to buy: Sold by Amazon

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Valerie Jacobsen writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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