Best magnesium supplement


According to the Mayo Clinic, magnesium plays a vital role in supporting nerve and muscle function. The mineral is also needed to support energy levels.

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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 supplement the mineral into their diet. Since all supplements are not created equally, choosing a quality option is paramount. 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 supplement

Quite a few people have difficulty swallowing large pills. If you experience challenges with larger pills, it is important to select a magnesium supplement that is smaller in size. 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. Thankfully, this doesn’t have to be the case. There are supplements that are specifically designed to mitigate all digestive discomfort. This is achieved by using a special kind of magnesium, and by creating the supplement with high-quality ingredients. Those who are prone to digestive discomfort should be aware of this possible side effect.


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 aligns with what your doctor has recommended for you. Magnesium pills are often set at lower amounts, which can be increased as needed.

Before starting supplementation with magnesium, always consult with your doctor. If you are taking other medicines, this is incredibly important to do. Magnesium can interact with specific types of medicines, such as blood pressure medication, diuretics and hormone replacement therapy. To avoid unpleasant or dangerous side effects, never take magnesium without seeking professional advice.

What to look for in a quality magnesium supplement


Across all kinds of supplements, one of the biggest hurdles is proper absorption. Those facing digestive conditions are especially prone to this issue. The ideal magnesium supplement will break 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. That is why it is essential to select a magnesium supplement that is designed to be properly absorbed by the body.

Pleasant effects

One unique aspect of magnesium supplements (when compared with other vitamin and mineral supplements) is the immediate benefits experienced. Oftentimes, those who begin taking magnesium 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 of this supplement.

How much you can expect to spend on magnesium supplements

Magnesium supplements range between $5-$40. Cost 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

Dr. Mercola Magnesium L-Threonate

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

What you’ll love: Because it uses a specific type of magnesium (magnesium L-threonate), this supplement does not act like a laxative. In addition to producing no digestive symptoms, Dr. Mercola Magnesium L-Threonate is designed for maximum mineral absorption.

What you should consider: Individuals who have trouble swallowing large pills can sometimes have problems with this supplement.

Where to buy: Sold by Amazon and iHerb

Top magnesium supplement for the money

Solaray Magnesium, 200 mg

Solaray Magnesium, 200 mg

What you need to know: Solaray Magnesium is an affordable and effective supplement that is 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 magnesium pill.

Where to buy: Sold by iHerb

Worth checking out

Nature Made Magnesium (Oxide) 250 mg Tablets

Nature Made Magnesium (Oxide) 250 mg Tablets

What you need to know: Nature Made Magnesium (Oxide) 250 mg Tablets is the most budget-friendly magnesium supplement on this list.

What you’ll love: This unflavored and gluten free magnesium supplement is held to the highest quality standards. It contains no artificial sweeteners, flavors or dyes. One bottle provides a 100-day supply for those who take 250 mg per day.

What you should consider: This supplement has a chalky taste and texture, which is undesirable to some.

Where to buy: Sold by Amazon and iHerb


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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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