Magnesium: Which form is best?
In recent months, magnesium has gained popularity on social media with many influencers directing you to a link to buy the supplements they recommend you take. While this is great, you have no idea what those supplements are, where they are manufactured and what processes or raw materials have been used. Most importantly, those influencers probably have no basic knowledge of nutrition, manufacturing processes and what makes one supplement better than another.
Very often, the supplements they promote are made in countries with inexistent quality standards or control (is the dosage meets the claim on the label? Does the dosage remain the same right until the expiry date? Are the ingredients used of any quality at all and usable by the body?). Indeed, a multitude of products on the market today does not deliver what the manufacturer claims on the label. In other words, many retailers sell low-quality, poorly absorbed supplements designed to maximize profits rather than health benefits.
Products dispensed by healthcare professionals are distinctly different. Plus, taking supplements without supervision may not offer the desired effect (why are you taking those supplements, how long for, when and how much?).
Your healthcare provider knows your medical history and is an expert in choosing the products you need.
The bioavailability of an active ingredient is the proportion of it that will actually be absorbed and assimilated by the body. The form in which an active ingredient is provided is, therefore, just as important as the quantity provided.
To make it even more difficult to assess, many manufacturers mention “elemental” or equivalent of the magnesium used, to label a greater availability and dosage — what is actually used by the body. That is because many manufacturers indicate a dosage that is not what the body can absorb and utilise.
Magnesium is vital for life. It is the fourth most abundant mineral in the body, required by every cell, and used as a cofactor in over 300 enzyme systems. And yet, studies estimate that as many as 75% of Americans do not get enough and that, globally, people do not meet the recommended daily intake. Since many people may require a greater intake, it has made magnesium such a popular supplement. But be careful; not all forms of magnesium are equal. Plus, some manufacturers package their supplements with additives that may decrease the bioavailability of magnesium. The fewer the ingredients in your supplements the better.
See the table below for more information.
-
Absorbability: High
Common Uses: To support a healthy nervous system and the stress response. Magnesium citrate displays a calming effect. Often used as a laxative and is not well-tolerated at a higher dose.*
Dietary Sources: Green leafy vegetables, nuts, seeds, whole grains.
Notes: A combination of magnesium and citric acid. A very budget-friendly option.
-
Absorbability: High
Common Uses: To support healthy energy production and to relax muscles. It may also be recommended for fibromyalgia and chronic fatigue syndrome.*
Dietary Sources: Apples, apricots, nuts, seeds.
Notes: Supports ATP production and cellular energy.
-
Absorbability: High
Common Uses: To support healthy stress response and sleep. It may also help with migraine. and display anti-inflammatory properties.*
Dietary Sources: Dark leafy greens, nuts, seeds, whole grains.
Notes: gentle on the stomach.
The combination of chelated magnesium and glycine (an amino acid), making this supplemental form one of the most bioavailable.
-
Absorbability: High
Common Uses: To support healthy blood sugar levels and heart health. It may also display anti-inflammatory properties and may help with modulating the stress response and migraines.*
Dietary Sources: Dark leafy greens, nuts, seeds, whole grains.
-
Absorbability: High
Common Uses: To support healthy cognition (can cross the blood-brain barrier) and mood.*
Dietary Sources: Dark leafy greens, nuts, seeds, whole grains.
Notes: Best taken in the morning and combine with other forms of magnesium for greater effect (often in low doses in capsules — one of the most expensive forms of magnesium).
-
Absorbability: High
Common Uses: To support healthy energy production and digestive and bone health.*
Dietary Sources: Fermented foods, leafy greens, whole grains.
-
Absorbability: High
Common Uses: To support healthy immune function, oxidative stress response (free radical damage), bone health, and mineral absorption.*
Dietary Sources: Citrus fruits, strawberries, broccoli, Brussels sprouts.
-
Absorbability: High
Common Uses: To support healthy energy production and antioxidant properties.*
Dietary Sources: Mushrooms, whole grains, meat, fish.
-
Absorbability: High
Common Uses: To support healthy stress response and skin health.*
Dietary Sources: Seaweed, nuts, seeds, dark chocolate, brassicas.
-
Absorbability: moderate
Common Uses: To relax muscles and healthy digestion. Best to combine it with other forms (e.g., Epsom salt + supplemental form).*
Dietary Sources: Epsom salt, seaweed, leafy greens, nuts, seeds.
Notes: often recommended for muscle tension/aches and cramps.
-
Absorbability: moderate/low
Common Uses: To support healthy muscle function and digestion (heartburn and/or constipation), and bone health*
Dietary Sources: Dark chocolate, nuts, seeds, legumes, whole grains.
Notes: can cause stomach upset.
* These statements have not been evaluated by the FDA/FSA. These products/statements are not intended to diagnose, treat, cure, or prevent any disease.
** Magnesium citrate and malate are considered Krebs cycle chelates and are, therefore, involved in cellular energy production. They are valuable because they may display higher bioavailability and absorption rates, and may provide additional support for maintaining healthy bodily systems and pathways. They are also best to take in the morning as they may be stimulating/energising.
*** Magnesium taurate is often combined with other forms of magnesium. Always look for a well-absorbed version.
Other forms of magnesium do not provide sufficient benefits and are thus not included here (e.g., magnesium carbonate).
Sources
1. National Institutes of Health. Office of Dietary Supplements. Magnesium. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/.
2. Higdon, J. Magnesium. Linus Pauling Institute. Oregon State University. https://lpi.oregonstate.edu/mic/minerals/magnesium.
3. Tucker KL, Hannan MT, Chen H, et al. Potassium, magnesium, and fruit and vegetable intakes are associated with greater bone mineral density in elderly men and women. Am J Clin Nutr. 1999;69(4):727-736. doi:10.1093/ajcn/69.4.727.
4. National Center for Biotechnology Information. PubChem Compound Summary for CID 9810651, Magnesium fumarate. https://pubchem.ncbi.nlm.nih.gov/compound/Magnesium-fumarate.
5. Magnesium Fumarate - an overview | ScienceDirect Topics. https://www.sciencedirect.com/topics/medicine-and-dentistry/magnesium-fumarate.