Magnesium bisglycinate is chelated: each magnesium ion is bound to two glycine molecules, so it travels through the gut intact instead of dissociating the way oxide does. That part is settled science, and it's why the form costs more to make.

The specific figure: in SHIME® laboratory digestion testing — a simulated human gut, run by the contract lab ProDigest — Chelamax® released 64% of its magnesium across the test membrane, against 46.7% for another leading bisglycinate at the same dose. That is a lab model, not a human trial, and results in people may differ. We publish it with that caveat attached because it is the data that exists, not because it settles anything. Worth knowing: no magnesium brand on the market has a head-to-head human absorption trial — including the ones printing bigger numbers than ours.

275 mg per serving of three capsules. That is 65% of the Daily Value, and it is printed on its own line in the Supplement Facts panel.

It is worth understanding why we phrase it that way, because this is where most magnesium shopping goes wrong. A label can quote two different numbers: the weight of the whole compound, or the magnesium inside it. Bisglycinate is roughly 11–14% magnesium by weight. L-threonate is about 7%. So a bottle reading "2,000 mg" on the front can deliver 144 mg of actual magnesium on the back. Both numbers are true; only the second one reaches you. Before buying any magnesium, ours included, turn the bottle around and find the line that says Magnesium with a % Daily Value beside it. That is the number that matters.

More common than the category admits. A noticeable share of people take magnesium expecting calm and get the opposite — a busier head, a faster pulse, broken sleep. It is reported most often with glycinate and threonate, the premium forms, rather than the cheap ones, and the suspected culprit is the glycine rather than the magnesium itself.

We are not going to tell you it cannot happen with ours. That is individual, and no brand can honestly promise otherwise. What we can do is make it inexpensive to find out. Start with one capsule instead of three for the first few nights, take it earlier in the evening rather than right at bedtime, and build up from there. If it still is not for you, the 90-day guarantee covers an opened bottle. You should not have to gamble full price to learn how your own body responds.

Magnesium's laxative effect comes mainly from magnesium that is not absorbed. It stays in the gut and draws water with it. That is why oxide and citrate have the reputation they do, and why chelated forms are generally gentler — more of the dose is taken up, so less of it remains behind to cause trouble.

Dose matters as much as form. The NIH sets an upper level of 350 mg per day for magnesium from supplements, and that ceiling exists because of the laxative threshold, not toxicity. Our serving is 275 mg, deliberately beneath it. Some well-known products ask for 400 mg a day at their labeled serving. If your stomach is sensitive, take it with food and begin with a single capsule.

This is chemistry rather than marketing. Fully chelated magnesium bisglycinate is roughly 11–14% magnesium by weight — the remainder is the glycine it is bound to, which is the entire point of the form. Delivering 275 mg of actual magnesium therefore takes close to two grams of raw material. No capsule holds that. A product promising a full dose in one pill is either using a form that carries more magnesium per gram and absorbs less of it, or quoting the compound weight on the front of the bottle.

What we could control is what those three are like to take. They are capsules, not tablets — a smooth shell rather than a compressed, chalky disc — and they are meant to go down together in one mouthful of water, once a day, in the evening. That is not a small detail. The single most common complaint across this entire category is not about results: it is people describing choking on tablets, cutting them into pieces, and quietly abandoning the bottle. A supplement you stop taking does not work.