Magnesium & Muscles

What you should look for in a magnesium supplement

a woman taking a tablet with a glass of water
Choosing the right magnesium supplement to support your health comes down to more than just comparing prices. Magnesium supplements come in many different forms, types and combinations and there can be great variability between magnesium products.
Here are some factors to consider when choosing between different magnesium supplements to assist your goals.


The different forms of magnesium explained

Magnesium needs to be bound to another molecule to increase its stability in a supplement. The molecule used can affect its bioavailability, or how well it is absorbed and used. In other words, can your body actually make use of it? There are many different forms of magnesium available on the market, but these are the most common ones you will likely come across in your search for the best magnesium supplement.

Magnesium oxide

Magnesium oxide is a combination of magnesium and oxygen. It’s cheaper to produce than other magnesium forms, however, it tends to have a low absorption rate, as low as 4% in some studies.1 This means it may be harder to achieve your intended health benefits. Magnesium oxide can also lead to unfortunate side effects like an upset stomach and loose bowel motions.

Magnesium citrate

Magnesium citrate is magnesium that’s bound to citric acid. Studies show that this type of magnesium is well absorbed when compared to other forms.2

Magnesium orotate

This is magnesium combined with orotic acid. This type of magnesium has a good absorption rate and is especially beneficial for cardiovascular health.3

Magnesium sulfate

This form of magnesium combines sulphur, oxygen and magnesium. It is more commonly known as epsom salts. It’s best used as a bath soak to help with muscle aches and pains as when taken orally it has a low absorption rate and a laxative effect.

Magnesium diglycinate (Meta Mag®)

Magnesium diglycinate (Meta Mag®) is magnesium combined with the amino acid glycine. It’s an easily absorbed form of magnesium that’s readily transported to the bloodstream. Evidence suggests that magnesium diglycinate has superior absorption when compared to other forms including magnesium oxide and magnesium citrate.4,5 Other key benefits of magnesium diglycinate are that it’s well-tolerated and gentle on the stomach and doesn’t have the uncomfortable digestive side effects associated with other magnesiums. It is also suitable for many different health applications from relieving muscle cramps and mild spasms to assisting energy production and providing benefits during times of stress.


What else should l look for in a magnesium supplement?

Aside from looking at the magnesium form and how well it’s absorbed and used by the body, there are other considerations.

The preparation (tablet/powder)

Your magnesium supplement will not be very effective if you do not take it. When choosing the right magnesium preparation for your lifestyle, have a think about whether you prefer the convenience of taking tablets or if you’d prefer the ease of a magnesium powder. Athletes and those who have trouble swallowing tablets might be better off with a powder formulation that can be made into a delicious and hydrating drink. People who lead busy lifestyles might favour magnesium tablets that can be taken on the go.


Elemental magnesium amount

The actual amount of magnesium in a supplement is known as the elemental amount and is usually provided in brackets on the label. This might be valuable when comparing magnesium supplements. Keep in mind that a supplement containing 500mg of a magnesium compound might only contain 50mg of actual magnesium.


Combination with other ingredients

Magnesium is often combined with other ingredients to enhance results. For example, to assist with sleep, magnesium might be combined with a calming herb such as passionflower. To support a healthy stress response, magnesium might be combined with the adaptogen rhodiola. Magnesium formulas may also include complementary nutrients such as B vitamins, zinc, vitamin C, vitamin D and taurine to assist energy production, support healthy muscles and relieve premenstrual symptoms and menstrual pain.


How to choose a magnesium supplement that’s best for your goals

Ethical Nutrients, Australia’s no. 1 magnesium brand, has a range of magnesium supplements to suit your unique situation. All formulas contain high strength, easily absorbed and tolerated magnesium diglycinate (Meta Mag®) to help you achieve the health goals you have in mind. You also have the choice between tablets and powders to help with compliance in meeting your magnesium targets and unique formulas designed to assist with different health needs like stress, sleep, energy and muscle health support. 



  1. Firoz M et al, 2001, ‘Bioavailability of US commercial magnesium preparations’, Magnes Res, vol 14, no 4, pp 257-62
  2. Kappeler D et al, 2017, ‘Higher bioavailability of magnesium citrate as compared to magnesium oxide shown by evaluation of urinary excretion and serum levels after single-dose administration in a randomized crossover study’, BMC Nutrition, vol 3, no 7
  3. Stepura O.B, 2009, ‘Magnesium orotate in congestive heart failure’ (MACH), Int.J Cardiol, vol 131, pp 293–295
  4. Hartle J et al 2016, ‘Development of a model for in-vitro comparative absorption of magnesium from five magnesium sources commonly used as dietary supplements’, FASEB Journal, vol 128, no 6
  5. Graff D 2000, ‘Bioavailability of magnesium chelazome’, Research Notes, vol 9, no 1, pp2-3

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