Magnesium: The Different Forms and What They Are For
Glycinate, citrate, oxide, and more. Magnesium supplements come in several forms and they are not interchangeable. A short guide to telling them apart.
Magnesium is involved in hundreds of enzyme reactions in the body, including those governing muscle and nerve function. When people shop for it, the confusing part is not whether to take magnesium, but which of the many forms to pick.
Why the form exists at all
Magnesium is a metal. It is not stable on its own in a tablet, so it is bound to another molecule. That partner molecule changes how well the compound dissolves, how much elemental magnesium you get per gram, and how it tends to affect digestion.
The common forms
- •Magnesium glycinate is bound to the amino acid glycine. It is well tolerated by most people and less likely to loosen the bowels, which is why it is often chosen for regular daily use.
- •Magnesium citrate is bound to citric acid. It dissolves readily and is well absorbed. It also has a mild laxative effect, which some people want and others do not.
- •Magnesium oxide contains a high percentage of elemental magnesium by weight but is poorly absorbed. It is inexpensive and commonly used where a laxative effect is the goal.
- •Magnesium malate and magnesium taurate are less common and are usually chosen for specific reasons on advice.
Check the elemental magnesium figure, not just the compound weight. A 500 mg magnesium citrate tablet delivers far less than 500 mg of actual magnesium.
Food sources
Before reaching for a supplement, it is worth knowing that magnesium is reasonably widespread in food:
- •Nuts and seeds, particularly pumpkin seeds and almonds
- •Whole grains
- •Dark leafy greens such as spinach
- •Legumes, including chickpeas and lentils
- •Dark chocolate
A note of caution
Magnesium supplements can interact with several medications, including some antibiotics and drugs used for osteoporosis and blood pressure. People with reduced kidney function should be particularly careful, because impaired kidneys clear magnesium less effectively.
If you take regular medication or have a kidney condition, check with your doctor or pharmacist before adding magnesium.
This article is general information about nutrition, not medical advice. Food supplements are not intended to diagnose, treat, cure, or prevent any disease. If you are pregnant, breastfeeding, taking medication, or managing a health condition, speak to your doctor or pharmacist before starting a supplement.
