There is no best magnesium.

That is an awkward sentence for a company that sells four of them, but it is the honest answer to the question almost everybody arrives with. “Which magnesium is best?” has no answer, in the same way that "Which shoe is best?” has no answer. The useful question is which one matches your reason for taking it at all.

Last month we asked you to make your routine smaller. This is the follow-up: if only two or three things are staying, they may as well be the right ones. Magnesium is where this gets confusing fastest, because the forms genuinely are not interchangeable, and very few guides explain the difference without quietly recommending all of them.

So here is the plain version, including the parts that are unflattering to us.

First, the number on the front of the bottle is not the number that matters

This is the single most useful thing in this article, so it goes first.

“500 mg magnesium glycinate” does not mean 500 mg of magnesium. It means 500 mg of the whole compound—the magnesium plus the glycine it is bound to. The magnesium itself is a fraction of that total.

The amount you actually want is the elemental magnesium, and it lives in the Supplement Facts panel on the back, not in the large type on the front. Two bottles can advertise the same impressive number and deliver quite different amounts of the mineral.

While you have the bottle turned around, check the serving size too. An impressive figure sometimes turns out to be spread across two or three capsules, which changes both the dose and what you are paying per day.

Three checks, in order: the form, the elemental amount, the serving size.

Do them to our bottles as well.

The four forms, side by side

That table is the whole article in miniature. The rest is detail.

Glycinate — the gentle one

Magnesium bound to glycine. This is the form most people reach for in the evening, and the one most often named in “what do you take at night” conversations.

It tends to be well tolerated, which is the main reason it gets recommended for daily use over cheaper forms. If your reason for taking magnesium is that you want one calm cue at the end of the day and you would like the supplement part of it to be uneventful, this is the reasonable starting point.

What we will not tell you is that it works like a switch. It does not.

Citrate — the digestion one

Magnesium bound to citric acid. It is the form usually chosen when the reason is digestion and regularity rather than evenings.

The thing to understand about citrate is that its most commonly reported effect and its most common complaint are the same effect. If regularity is what you are after, that is a feature. If you were hoping for a quiet evening capsule and chose citrate because it was on offer, you may find it more eventful than you wanted. Start low, follow the label directions, and take it at a time of day that suits you rather than the internet.

Complex — the no-decisions one

A blend of forms rather than a single one, aimed at broad daily coverage.

Complex exists for a specific kind of person: someone who does not want to run a comparison, does not have one dominant reason, and would like to take one capsule and stop thinking about it. That is a perfectly good reason to choose it. Just read the panel, because “complex” is a description of a strategy, not a standardized recipe—the mix varies between brands, ours included.

Gummies — the one you will actually finish

Here is the unflattering part we would rather say out loud: gummies generally carry less magnesium per serving than capsules, and they usually come with some added sugar.

And they are still the right choice for a lot of people, because the best format is the one still in your hand in six weeks. A cabinet with three unfinished bottles of capsules in it is not evidence of a discipline problem. It is evidence that the format was wrong. If chewing something at the end of the day is the difference between a routine you keep and one you abandon by Thursday, the trade-off is worth it.

What the research does and does not show

This is the section most magnesium guides skip, so we will be specific.

Reasonably well established: magnesium is an essential mineral involved in a very large number of processes in the body, and a meaningful share of adults take in less than the recommended amount from food. That is the sturdy part of the story, and it is the honest reason to consider a supplement at all.

Suggestive, not settled: almost everything the internet finds exciting. Where sleep, calm, and mood are concerned, the research is mixed, the studies are often small, and the people who benefit most in trials tend to be those who were low to begin with. There is enough there to make it a sensible thing to try. There is not enough there for anyone to promise you a result, and we are not going to.

Not established, and not something we will claim: that magnesium treats, cures, or prevents any condition, that it fixes hormones, or that it produces weight loss. If you see a brand implying otherwise, that is a marketing decision, not a scientific one.

One more piece of honesty about form comparisons specifically: much of the ranking of forms you will read online—including some of what we have written above—reflects tolerability, common usage, and reasonable inference more than large head-to-head human trials, which mostly do not exist. Glycinate being the popular evening choice is real. Glycinate being proven superior for sleep is not a claim anyone can currently make.

When should you take it?

The genuinely evidence-based answer is duller than you want: at a time you will actually remember, consistently, according to the label directions.

Beyond that, most people take glycinate or complex in the evening, and most people take citrate at whatever time of day makes its digestive effect convenient rather than surprising. Some prefer taking it with food. Attach it to something you already do—brushing your teeth, closing the laptop, the same last glass of water—because an anchored habit survives a bad week, and an aspirational one does not.

If you are taking any prescription medication, check with your pharmacist about timing. Some medications and minerals are better kept apart, and a pharmacist will answer that in about a minute.

When magnesium is not the answer

Sometimes it is not, and we would rather say so than sell you a fourth bottle.

• When you are sleeping badly because of your schedule. An inconsistent wake time, a late caffeine cutoff, a warm bright bedroom, or a phone in your hand at midnight will out-argue any capsule. The free structural habits carry far more weight than the supplement aisle does, which is inconvenient for us and true anyway.
• When you are already taking magnesium in something else. Check your multivitamin, your electrolyte powder, and your greens blend before adding another source. Duplicated minerals are common and rarely intentional.
• When you have not given the one you own a fair run. If there is a half-used bottle in the drawer, finish that before buying a different form. The bottle you finish beats the bottle you upgrade to.
• When something needs a clinician, not a supplement. Persistent exhaustion, ongoing insomnia, significant digestive changes, or new symptoms are worth a conversation with a doctor. A supplement is a poor substitute for a diagnosis.
• When you cannot say what it is for. If you cannot finish the sentence “I take this because…”, that is a good sign it belongs in the pause pile rather than the routine.

The short version

Pick the form that matches your reason. Check the elemental amount and the serving size on the back panel. Anchor it to something you already do, take it according to the label directions, and give it a fair, boring run before deciding anything.

We sell all four forms, and we still think you should only be taking one.

🩺 This article is general educational information, not medical advice. If you are pregnant, nursing, taking prescription medication, or managing a health condition—particularly anything involving your kidneys or heart—talk to your doctor or pharmacist before starting a magnesium supplement. Always use supplements according to their label directions.