Which Magnesium Should You Choose? Glycinate, Citrate or Lactate — Comparing the Forms

Below we go through each of the five forms individually — because while the table shows the differences at a glance, it doesn't explain WHERE they come from, and that's exactly the knowledge that lets you judge consciously whether a particular product on the shelf actually fits your goal.

Magnesium glycinate is magnesium bound to glycine — an amino acid that on its own has a mild calming effect and supports sleep quality. It's probably this synergy between the two components, not magnesium alone, that explains why this particular form is so often recommended in the evening rather than, say, citrate with similar bioavailability. An additional advantage of glycinate is very good gastrointestinal tolerance — chemically, it's a chelated compound, meaning the magnesium is 'wrapped' in the amino acid molecule rather than appearing as a free ion irritating the intestinal lining.

Magnesium citrate is magnesium bound to citric acid — one of the best-studied and most widely available organic forms, with bioavailability comparable to glycinate but usually at a noticeably lower price. It's precisely this lack of 'specialization' that makes it a good all-purpose choice: there's no extra component steering its effect (like the glycine in glycinate), so it works well as baseline supplementation for a plain, general deficiency, without an additional goal like improving sleep.

It's worth knowing that at higher doses, magnesium citrate has a somewhat stronger osmotic effect in the gut than glycinate, which in some people can show up as slightly looser stools — for most people this isn't an issue at typical doses, but it's worth being aware of, especially with large single-serving doses.

Magnesium lactate (bound to lactic acid) appears less often in Polish advertising than glycinate or citrate, but it has very good absorption and is one of the gentler forms on the stomach — which is why it's often recommended for people who experience digestive discomfort with other forms of magnesium but don't want to reach for the pricier glycinate.

Magnesium malate (bound to malic acid) stands out because malic acid itself participates in the Krebs cycle — the intracellular energy-production process — which gives a theoretical rationale for this form's popularity among people looking for support with feelings of fatigue. Evidence for this extra energy-related effect is still preliminary, though, and rests mainly on biochemical logic rather than on large clinical trials directly comparing malate with other forms of magnesium for perceived energy.

Magnesium oxide, despite being the cheapest and most common form in inexpensive pharmacy products, has one of the lowest bioavailabilities among the available forms — a large part of the dose isn't absorbed and acts mainly as a laxative, which is actually deliberately exploited in products for constipation rather than for deficiency supplementation. In other words: if the label lists 'magnesium oxide' as the only form, you're probably paying for magnesium a significant portion of which will leave your body before it has a chance to be absorbed.

For most people without a specific additional goal (like improving sleep), magnesium citrate remains a reasonable, well-studied default choice — good absorption at a relatively low price. Glycinate pulls ahead wherever the priority is evening relaxation support rather than simply correcting a deficiency.