Magnesium glycinate vs citrate: which form should you take?

Magnesium glycinate and citrate are both well-absorbed organic forms, so the practical question isn't "which is better" — it's which side effect you want. The experts draw the line at the gut.

Attia is the clearest on this. He groups citrate, glycinate, and oxide together as forms that "speed up the bowel," and says that if you *don't* want a laxative effect you should reach for magnesium carbonate instead. That makes citrate a reasonable pick if you're also dealing with constipation, and a worse one if you're not. Attia himself rotates several forms to hit roughly a gram of elemental magnesium a day.

For sleep and calm, glycinate is the form that comes up repeatedly. Hyman favors glycinate and citrate as well-absorbed chelates and specifically warns against magnesium oxide as a "cheap," poorly absorbed form. Huberman's sleep stack uses magnesium threonate or bisglycinate (a close cousin of glycinate) for sleep latency and depth, and he reserves malate for gut health and recovery. Patrick recommends the organic salts — citrate, glycinate, taurate — in smaller divided doses.

Two honest caveats. First, magnesium threonate is popular for "brain" benefits, but Patrick notes its elemental magnesium content is low and its clinical evidence is limited and industry-funded — so it's a cognition/sleep add-on, not a way to hit your daily magnesium target. Second, the experts converge on avoiding oxide for daily supplementation because so little is absorbed. Where they diverge is carbonate: Attia likes it precisely because it doesn't loosen the bowel, while Hyman lumps it in with the cheap forms to avoid — a genuine disagreement worth knowing before you buy.