Every Type of Magnesium Compared: Which Form Is Best for Your Goal?

Updated 11 April 2026

There are over 10 different forms of magnesium, each with different absorption rates, side effects, and ideal uses. This page compares them all with a clear recommendation for each health goal.

Quick Reference Table

FormBioavailabilityBest useGI tolerancePrice
Glycinate25-35%Sleep, anxiety, stress, sensitive stomachsExcellent$$
Citrate25-35%Constipation, general repletion, budget optionModerate$
Threonate (L-Threonate)HighCognitive function, memory, brain healthGood$$$
Taurate20-30%Heart health, blood pressure, anxiety with heart concernsGood$$
Malate20-30%Energy, muscle pain, fibromyalgiaGood$-$$
Oxide4-5%Budget laxative (not recommended for supplementation)Poor$
Chloride20-30%Topical use (oil/flakes), oral supplementationGood$-$$
Sulfate (Epsom Salt)Low (oral)Bath soaks, muscle relaxation (topical)Poor (oral)$
OrotateModerateCardiovascular health, athletic performanceGood$$$
L-AspartateModerateGeneral supplementationModerate$$

Detailed Profiles

Magnesium Glycinate

Best for sleep and anxiety

Magnesium bonded to glycine, an amino acid with calming and neuroprotective properties. The dual-action mechanism (magnesium + glycine) makes it uniquely effective for sleep and anxiety. Gentlest on the stomach of all forms. Higher cost due to complex chelation manufacturing process.

Bioavailability

25-35%

GI tolerance

Excellent

Price tier

$$

Best for

Sleep

Magnesium Citrate

Best for constipation and value

Magnesium bonded to citric acid. Excellent water solubility and good absorption. The osmotic laxative effect makes it the go-to for constipation relief. Affordable and widely available. May cause loose stools at higher doses.

Bioavailability

25-35%

GI tolerance

Moderate

Price tier

$

Best for

Constipation

Magnesium Threonate (L-Threonate)

Best for brain health

The only magnesium form demonstrated to cross the blood-brain barrier effectively. Developed at MIT and patented as Magtein. Studies show it increases brain magnesium levels and improves learning, memory, and cognitive function. Significantly more expensive than other forms but serves a unique purpose.

Bioavailability

High

GI tolerance

Good

Price tier

$$$

Best for

Cognitive function

Magnesium Taurate

Best for heart health

Magnesium bonded to taurine, an amino acid that supports cardiovascular function and has calming properties. Studied for blood pressure reduction and cardiac rhythm stability. A good alternative to glycinate if you have anxiety combined with heart health concerns.

Bioavailability

20-30%

GI tolerance

Good

Price tier

$$

Best for

Heart health

Magnesium Malate

Best for energy and muscle pain

Magnesium bonded to malic acid, which plays a key role in the Krebs cycle (cellular energy production). Some evidence suggests benefit for fibromyalgia and chronic fatigue. Well-tolerated and reasonably priced. A good all-purpose option if energy is a concern.

Bioavailability

20-30%

GI tolerance

Good

Price tier

$-$$

Best for

Energy

Magnesium Oxide

Not recommended

The cheapest and worst-absorbed form. Contains the highest elemental magnesium per capsule (60%) but only 4 to 5% is actually absorbed. More likely to cause GI side effects. Useful only as a budget laxative. Not recommended for correcting deficiency or therapeutic use.

Bioavailability

4-5%

GI tolerance

Poor

Price tier

$

Best for

Budget laxative (not recommended for supplementation)

Magnesium Chloride

Best for topical + oral flexibility

Good bioavailability in oral form. Also available as magnesium oil for topical application and bath flakes. The oral form was used in the Tarleton 2017 study that showed benefit for depression and anxiety. A versatile, well-absorbed option.

Bioavailability

20-30%

GI tolerance

Good

Price tier

$-$$

Best for

Topical use (oil/flakes)

Magnesium Sulfate (Epsom Salt)

Topical use only

Primarily for topical use in baths and soaks. Oral absorption is poor and can cause significant GI distress. IV magnesium sulfate is the medical standard for eclampsia treatment. As a supplement, there are much better options.

Bioavailability

Low (oral)

GI tolerance

Poor (oral)

Price tier

$

Best for

Bath soaks

Magnesium Orotate

Niche use for athletes

Magnesium bonded to orotic acid, which is involved in DNA and RNA synthesis. Some research suggests benefit for cardiovascular conditions and exercise performance. Expensive and less commonly available. Limited research compared to glycinate and citrate.

Bioavailability

Moderate

GI tolerance

Good

Price tier

$$$

Best for

Cardiovascular health

Magnesium L-Aspartate

Adequate general option

Magnesium bonded to aspartic acid. Decent bioavailability. Often found in combination supplements (like ZMA, which combines zinc, magnesium aspartate, and B6). Less studied than glycinate or citrate for specific health goals.

Bioavailability

Moderate

GI tolerance

Moderate

Price tier

$$

Best for

General supplementation

Decision Matrix: If Your Goal Is X, Take Y

Your goalFirst choiceAlternative
Better sleepGlycinateThreonate
Reduce anxietyGlycinateTaurate
Constipation reliefCitrateOxide (budget)
Muscle crampsGlycinate or CitrateMalate
Pregnancy supportGlycinateCitrate (for constipation)
Cognitive functionThreonateGlycinate
Heart healthTaurateGlycinate
Energy and fatigueMalateCitrate
Athletic performanceMalate or OrotateGlycinate
General deficiencyCitrateGlycinate
Budget optionCitrateChloride
Topical useChloride (oil/flakes)Sulfate (Epsom salt)

Disclaimer: This content is for educational purposes only. Consult your healthcare provider before starting any supplement, especially if you take medications or have health conditions.

Frequently Asked Questions

Which type of magnesium is best overall?
There is no single best type. Glycinate is best for sleep and anxiety. Citrate is best for constipation and general repletion. Threonate is best for cognitive function. Taurate is best for heart health. Choose based on your primary goal.
What is the most bioavailable form of magnesium?
Glycinate, citrate, and chloride are all highly bioavailable (20 to 35%). Threonate also has high bioavailability and uniquely crosses the blood-brain barrier. Oxide has the worst bioavailability at 4 to 5%.
Is magnesium threonate worth the price?
If cognitive function, memory, or brain health is your primary concern, threonate is the only form studied specifically for crossing the blood-brain barrier. It is significantly more expensive than glycinate or citrate but serves a unique purpose that no other form does.
Can I take two different forms of magnesium?
Yes. Many people take glycinate at night for sleep and citrate in the morning for digestive support. Just keep your total daily elemental magnesium under 400 mg from supplements and take them at separate times.
Why is magnesium oxide still sold if it is poorly absorbed?
Because it is the cheapest to manufacture and has the highest elemental magnesium per capsule. Manufacturers can put a large number on the label. Consumers who do not understand bioavailability buy it based on the high milligram count. It is primarily useful as a cheap laxative.
What form of magnesium is in Epsom salt?
Magnesium sulfate. It is intended for topical use (bath soaks) and is poorly absorbed orally. Evidence for transdermal magnesium absorption through bath soaking is limited and not well established.