Medically reviewed by Dr. Reina Punj, MBBS, PG Diploma in Endocrinology (University of South Wales), Lead Physician, Excelgenics Clinical Panel.
Magnesium glycinate and magnesium bisglycinate are, in practice, two names for the same compound: magnesium bound to two molecules of the amino acid glycine. "Bisglycinate" (also written "diglycinate") spells out the two glycines; "glycinate" is the shorter everyday name. So if you are comparing magnesium glycinate vs bisglycinate, the more useful questions are how much elemental magnesium a product gives you and what else is in the tablet.
This article explains what "chelated magnesium glycinate" means, how to read the label, and how this form compares with citrate and oxide. For a broader overview, see our Magnesium Supplements Guide.
Is magnesium bisglycinate the same as magnesium glycinate?
Yes, chemically they describe the same substance. Chemical reference sources list magnesium diglycinate, magnesium glycinate and magnesium bisglycinate as names for the same compound. Its formula is C4H8MgN2O4: one magnesium atom and two glycinate groups.
The word "bis" simply means "two". Manufacturers and regulators tend to use the longer name because it is more precise; for example, the European Food Safety Authority's 2008 opinion on mineral sources refers to "bisglycinates" as sources of magnesium, calcium, zinc and copper. Shops and search engines tend to use the shorter one. You may also see "magnesium glycinate bisglycinate" on a label, which is just both names together.
So when you search for magnesium bisglycinate and magnesium glycinate, you are looking at the same ingredient family. Differences between products come from dose, purity and formulation, not from the name.
What "chelated magnesium glycinate" means
A chelate (from the Greek for "claw") is a compound in which a mineral is held by a carrier molecule at more than one point. In magnesium bisglycinate, each glycine binds the magnesium through two sites, forming ring-shaped structures. That is why it is often called an "amino acid chelate" or "chelated magnesium".
"Chelated" describes the chemical structure. On its own, it does not tell you how much magnesium a tablet contains or how well it will be absorbed by a particular person.
Magnesium bisglycinate vs magnesium glycinate on the label: elemental vs compound weight
This is where most confusion happens. A label can show two different numbers:
- Compound weight: the weight of the whole magnesium bisglycinate ingredient, glycine included.
- Elemental magnesium: the weight of the magnesium itself, which is the figure that counts towards your daily intake.
Because glycine is much heavier than magnesium, the compound weight is always several times larger than the elemental magnesium it provides. A tablet listing "1,000 mg magnesium glycinate" does not give you 1,000 mg of magnesium. The exact share of magnesium also varies from one raw material to another, so you cannot reliably work it out yourself from the compound weight.
How to read a magnesium label
- Find the elemental figure. Look for wording such as "providing X mg elemental magnesium" or "magnesium (as bisglycinate) X mg". If only the compound weight is shown, ask the brand for the elemental amount before comparing.
- Check the serving size. Some products state the dose for two or more tablets.
- Read the full ingredient list. If other magnesium compounds, such as magnesium oxide or citrate, appear alongside the glycinate, part of the magnesium comes from those forms.
- Compare against the limit. The US National Institutes of Health (NIH) sets a tolerable upper limit of 350 mg a day of magnesium from supplements for adults. Food magnesium does not count towards this.
For example, Magneva Magnesium Bisglycinate 350mg + Vitamin B6 provides 350 mg of elemental magnesium per tablet, alongside 1.9 mg vitamin B6, at one vegan tablet a day. Since that is the full NIH upper limit for supplemental magnesium, it should not be combined with other magnesium supplements unless your doctor advises it.
Buffered vs fully reacted magnesium glycinate
You may see the terms "fully reacted" and "buffered" on product pages:
- Fully reacted is used to mean that the magnesium in the ingredient is all present as the glycine chelate.
- Buffered is used to mean the glycinate has been blended with another magnesium compound, most often magnesium oxide. This packs more magnesium into a smaller tablet, but some of the magnesium is then in the oxide form.
Neither term is a regulated label claim in India, and labels do not always say which type is used. If it matters to you, the ingredient list and the brand's specification are the places to check. A buffered product is not unsafe; it simply means you are getting a mix of forms rather than glycinate alone.
How does glycinate compare with citrate and oxide?
Absorption research on magnesium forms is limited, and studies are small. The NIH Office of Dietary Supplements notes that forms that dissolve well in liquid tend to be absorbed better, and that small studies have found the aspartate, citrate, lactate and chloride forms more completely absorbed than oxide and sulfate.
The best-known head-to-head study is Walker and colleagues (2003). In 46 healthy adults taking 300 mg elemental magnesium a day for 60 days, both the amino acid chelate and citrate groups excreted more magnesium in urine than the oxide group, a sign of greater absorption. Magnesium citrate, however, gave the highest blood and saliva magnesium levels, and the authors concluded that citrate was the more bioavailable form in their study. The chelate was not shown to be better absorbed than citrate.
So the honest summary is:
| Form | What the evidence suggests |
|---|---|
| Magnesium glycinate / bisglycinate | Organic chelate; in one small study, absorbed better than oxide but not better than citrate. Commonly chosen for daily evening use. |
| Magnesium citrate | Well absorbed in small studies; can have a laxative effect at higher doses. |
| Magnesium oxide | High magnesium content by weight but less well absorbed; more often linked with loose stools. |
People often choose glycinate because many find it gentle on the stomach, though individual tolerance varies. For a fuller comparison, read Magnesium Bisglycinate vs Citrate vs Oxide: Which Form Actually Works?, and for a buying checklist see How to Choose a Magnesium Bisglycinate Supplement in India.
What magnesium does in the body
Magnesium is involved in hundreds of enzyme reactions, including those for energy production, muscle function and nerve signalling. Magnesium contributes to a reduction of tiredness and fatigue. India's Recommended Dietary Allowance (ICMR-NIN 2020) is 440 mg a day for adult men and 370 mg for adult women from all sources, and nuts, seeds, whole grains, pulses and green leafy vegetables are good food sources.
Safety in brief
Common side effects of magnesium supplements are loose stools, nausea and stomach cramps. Speak to your doctor first if you have kidney disease, are pregnant or breastfeeding, or take medicines such as tetracycline or quinolone antibiotics, bisphosphonates, diuretics or long-term acid-reducing medicines (PPIs). The NIH advises taking these antibiotics at least 2 hours before or 4–6 hours after a magnesium supplement, and separating bisphosphonates from magnesium by at least 2 hours.
Frequently asked questions
Which is better, magnesium glycinate or bisglycinate?
Neither is better, because they are the same compound under two names. Compare products on elemental magnesium per serving, the full ingredient list and whether the dose stays within the 350 mg supplemental limit.
Is chelated magnesium the same as magnesium glycinate?
Not always. "Chelated magnesium" means magnesium bound to a carrier molecule such as an amino acid. Magnesium glycinate is one type of chelate, but a label saying only "chelated magnesium" may use a different carrier. Check the ingredient list for the exact form.
Why is the magnesium bisglycinate amount on the label so much higher than the magnesium amount?
The first figure is the weight of the whole compound, including the glycine. Only the elemental magnesium figure tells you how much magnesium you actually get.
Is magnesium glycinate better absorbed than other forms?
The evidence is limited. In one small study, an amino acid chelate was absorbed better than oxide, but citrate came out best overall. There is no strong evidence that glycinate is absorbed better than citrate.
References
- National Institutes of Health, Office of Dietary Supplements. Magnesium: Fact Sheet for Health Professionals. ods.od.nih.gov
- Walker AF, Marakis G, Christie S, Byng M. Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study. Magnesium Research. 2003;16(3):183–191. PubMed 14596323
- European Food Safety Authority. Opinion on certain bisglycinates as sources of copper, zinc, calcium, magnesium and glycinate nicotinate as source of chromium in foods intended for the general population. EFSA Journal. 2008;6(6):718. doi:10.2903/j.efsa.2008.718
- National Library of Medicine. PubChem compound summary: Magnesium glycinate. pubchem.ncbi.nlm.nih.gov
- ICMR-National Institute of Nutrition. Nutrient Requirements for Indians: Recommended Dietary Allowances and Estimated Average Requirements. 2020.
This article is for general education and is not medical advice. Food supplements are not intended to diagnose, treat, cure or prevent any disease. Consult a qualified healthcare professional before starting any supplement, particularly if you are pregnant, breastfeeding, have a medical condition or take medication.
