Types of Magnesium Supplements - A Pharmacist's Guide to Magnesium Glycinate vs Magnesium Citrate
Magnesium is the fourth most common mineral found in our body and is involved in more than 300 enzymatic reactions. It is essential for protein synthesis, muscle contraction, blood glucose control, regulating blood pressure, normal nerve function, cell division and energy production.
Magnesium can be obtained through our diet. Dietary sources of Magnesium include nuts, whole grains, such as brown rice and grain products, fish, seafood, several vegetables, legumes, and berries.
Although Magnesium can be obtained from many different groups, there is an unprecedented rise in Magnesium deficiency in the Western world.
Experts suggest the rise in Magnesium deficiency is most likely due to the:
- Higher processing of foods,
- Lower soil levels of Magnesium used to grow our vegetables,
- Reduced absorption of Magnesium due to Vitamin D deficiency,
- Medicines such as Diuretics, Antacids, and certain Antibiotics can reduce Magnesium levels, and
- Alcohol and caffeine - can increase magnesium excretion.
Signs of Magnesium Deficiency
The following signs and symptoms should be used as a guide only.
- Nausea, vomiting
- Muscle cramps and/or spasms
- Fatigue, weakness
- Unable to think clearly
Which type of Magnesium is best?
There are many different forms of Magnesium, each with its own unique characteristics.
Magnesium Citrate is found to have much greater bioavailability when taken on an empty stomach compared to Magnesium Oxide. It also has a mild laxative effect by attracting water into the colon.
Magnesium Ascorbate is a Magnesium compound bound attached to Ascorbic Acid. When Magnesium is coupled with buffered Vitamin C, it improves the oral bioavailability of Magnesium and reduces gastrointestinal discomfort.
Magnesium Diglycinate is a chelated form of magnesium and the amino acid glycine. The presence of glycine improves the solubility of the entire compound hence, increasing its bioavailability. The presence of glycine provides a calming effect to the nervous system, making it ideal to aid sleep.
The difference between Magnesium Glycinate and Magnesium Diglycinate is the latter has two glycine amino acids attached. Some studies suggest the diglycinate form exhibit greater bioavailability.
Magnesium Oxide has a very low absorption rate due to its low solubility. Supplements formulated with Magnesium Oxide or Magnesium Hydroxide will tend to be larger in size to make up for their low bioavailability. In a powder form, consumers will have to take higher dose.
Magnesium Chloride is a magnesium salt bound to chlorine. It is completely ionized across a large pH range, from pH 2 (found in stomach acid) to pH 7.4 (found in blood and lymph) and is well absorbed.
The chloride part of the compound produces Hydrochloric Acid in the stomach to enhance its absorption. This is useful for anyone with low stomach acid (production of stomach HCl is known to decline with age) or taking antacids.
Magnesium Chloride is also well absorbed via the skin, making it an ideal form for topical applications such as magnesium sprays and magnesium oils.
Magnesium Sulfate can be found in supplements commonly known as Epsom Salts to relieve sore muscles. Magnesium Sulfate has poor oral bioavailability.
There are many ways to use magnesium supplements and choosing a product can be confusing. Nonetheless, we hope this summary is useful when it comes to choosing your next magnesium supplement.
As always, check with your healthcare professional before starting on any supplement to ensure it is appropriate for you.
Author:Helen Huynh (B.Pharm) MPS
- Magnesium: Fact Sheet for Health Professionals. National Institute of Health. Published August 202. Access: https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
- What you should know about magnesium. Harvard Health Publishing. Published December 2017. Access: https://www.health.harvard.edu/staying-healthy/what-you-should-know-about-magnesium2