Quick Summary

Magnesium glycinate is a chelated form of magnesium commonly used as a dietary supplement to support magnesium intake. Magnesium itself is an essential mineral involved in a wide range of physiological functions necessary for overall health.

What Is It?

Magnesium glycinate is a compound consisting of magnesium bound to the amino acid glycine. This chelated form is designed to improve absorption and reduce potential gastrointestinal side effects often linked to other magnesium salts. It is primarily used to provide supplemental magnesium for individuals who may require increased intake or who have difficulty obtaining sufficient magnesium from their diet.

Main Functions in the Body

  • Supports normal muscle and nerve function
  • Participates in energy production and numerous enzyme reactions
  • Contributes to structural development and maintenance of bone
  • Helps maintain a normal heart rhythm

Recommended Intake and Upper Limit

Recommended dietary allowances (RDAs) for magnesium vary by age, sex and life stage. Adult requirements typically range between 310–420 mg/day of elemental magnesium from all sources including diet and supplements.

The Tolerable Upper Intake Level (UL) for magnesium from supplements and medications is set at 350 mg/day for adults. Exceeding this dose may increase the risk of adverse effects, particularly gastrointestinal discomfort such as diarrhea.

Values vary significantly by age, sex, and physiological state (e.g., pregnancy). For personalized recommendations, consultation with a healthcare professional is advisable.

Best Food Sources

  • Green leafy vegetables (e.g., spinach, kale)
  • Nuts and seeds (e.g., almonds, pumpkin seeds)
  • Whole grains (e.g., brown rice, whole wheat)
  • Legumes (e.g., beans, lentils)
  • Fortified foods

Deficiency: Causes, Symptoms and Risk Groups

Dietary magnesium deficiency is uncommon but can occur due to poor absorption, increased losses, or certain medical conditions. Groups at higher risk include:

  • Individuals with gastrointestinal diseases (e.g., Crohn’s disease, celiac disease)
  • People with type 2 diabetes
  • Elderly persons, who may have reduced intake or absorption
  • Individuals with alcohol dependence
  • Those using certain medications such as diuretics or proton pump inhibitors

Signs and symptoms potentially associated with magnesium deficiency include:

  • Muscle cramps and weakness
  • Fatigue
  • Cardiac arrhythmias
  • Numbness and tingling sensations

When magnesium deficiency is suspected, clinical evaluation and laboratory testing by a healthcare professional are recommended.

Supplement Forms

Magnesium is available in various supplemental forms, some of which include:

Magnesium glycinate is notable as a chelated form often chosen for potentially improved tolerance.

Absorption and Bioavailability

Magnesium glycinate is a chelated form of magnesium, meaning the mineral is bound to glycine, an amino acid. This chelation can enhance the mineral’s absorption and bioavailability compared to some inorganic forms such as magnesium oxide. However, high-quality, direct comparative human studies are limited.

Factors influencing magnesium absorption include:

  • Enhancers: normal stomach acid levels and adequate overall dietary intake
  • Inhibitors: phytates and oxalates found in various plant foods; high doses of competing minerals may also reduce absorption

Compared to inorganic magnesium salts, chelated forms like magnesium glycinate may cause fewer gastrointestinal side effects and are generally better tolerated, although individual responses may vary.

Potential Benefits: What Does the Evidence Say?

Correction of Magnesium Deficiency:

There is strong evidence that magnesium supplementation, including forms such as magnesium glycinate, can effectively correct deficiencies and alleviate related symptoms. This benefit is well supported in individuals with confirmed low magnesium status.

However, the specific comparative efficacy of magnesium glycinate versus other supplement forms is not well established due to limited direct research.

Side Effects and Toxicity

Common side effects of magnesium supplementation may include:

  • Diarrhea
  • Abdominal cramping

Excessive magnesium intake from supplements can cause gastrointestinal symptoms and, in rare cases, more serious magnesium toxicity. This risk is increased in persons with impaired kidney function, as their ability to excrete magnesium is reduced.

It is important not to exceed the UL of 350 mg/day from supplements without medical supervision.

Pregnant and breastfeeding women or individuals with kidney impairment should consult healthcare providers before supplementation.

Drug and Nutrient Interactions

There is limited specific evidence regarding drug interactions with magnesium glycinate. In general, magnesium supplements can interfere with the absorption of certain medications such as some antibiotics and bisphosphonates, so timing of supplementation and medications is an important consideration discussed with a healthcare provider.

Who Should Be Careful?

  • Individuals with renal impairment or kidney disease, due to risk of magnesium accumulation
  • Pregnant and breastfeeding women should seek medical advice before starting supplements
  • People taking medications that may interact with magnesium (e.g. diuretics, proton pump inhibitors, antibiotics)
  • Persons with pre-existing medical conditions affecting magnesium metabolism (e.g. thyroid disorders, iron overload)

Frequently Asked Questions

  • Is magnesium glycinate better absorbed than other forms?
    Magnesium glycinate is generally considered to have better bioavailability and fewer gastrointestinal side effects compared to some inorganic forms like magnesium oxide. However, robust comparative human studies are limited.
  • Can magnesium glycinate prevent muscle cramps?
    Magnesium plays a role in muscle function, and correcting deficiency may help reduce cramps. Evidence supporting supplementation for cramp prevention in people without deficiency is limited.
  • What is the difference between magnesium glycinate and magnesium citrate?
    Both are forms of magnesium supplements; glycinate is chelated with glycine and may be gentler on the stomach, whereas citrate may act as a mild laxative. Choice may depend on individual tolerance.
  • Can I take magnesium glycinate if I have kidney disease?
    People with kidney disease should consult a healthcare professional before taking magnesium supplements due to potential risks of accumulation and toxicity.
  • What is the safe upper limit for magnesium supplements?
    The Tolerable Upper Intake Level (UL) for magnesium from supplements is 350 mg/day for adults. Do not exceed this without medical supervision.

Evidence Limitations

  • There is limited direct clinical trial evidence comparing the absorption and efficacy of magnesium glycinate to other supplement forms.
  • No specific authorized health claims within the European Union have been identified for magnesium glycinate as a distinct supplement form.
  • Most evidence on magnesium’s physiological role and supplementation benefits relates to magnesium as a nutrient generally, rather than glycine-chelated magnesium specifically.

References

Disclaimer: This page provides information based on current scientific evidence but does not constitute medical advice. People who are pregnant, breastfeeding, have medical conditions (including kidney or thyroid disease), or take medications should consult a healthcare professional before starting magnesium supplementation.

Last reviewed: June 2024