Magnesium Bisglycinate 300mg — 24h Extended Release

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Magnesium bisglycinate · 300mg · 30 capsules

Magnesium Bisglycinate 300mg — 24h Extended Release

$34.89~~$44.89~~Save up to 25%

One capsule a day of the form your stomach doesn’t argue with — released across the whole day instead of all at once.

Bisglycinate form

24h extended release

30 days, one capsule

Choose your supply

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Secure checkout · Ships in 1–2 business days

Take it, or send it back.

Finish the bottle. If it did nothing for you, tell us and we’ll refund it — empty bottle and all. We’d rather lose the sale than keep money from someone it didn’t help.

The problem with most magnesium

Most magnesium leaves
before it does anything.

The cheap bottles are almost always magnesium oxide. It’s cheap because it’s easy to make and easy to print a big number on — and it’s poorly absorbed. Much of what you swallow never crosses into you. It sits in the gut, draws water in behind it, and leaves the way it came.

Which is why most people’s first experience of magnesium is an unsettled stomach and no noticeable difference — and why they conclude magnesium doesn’t work for them. Usually it wasn’t the mineral. It was the form.

The form

Bound to an amino acid,
not to a rock.

Magnesium bisglycinate is magnesium attached to two molecules of glycine — an amino acid your body already has dedicated machinery to absorb. Instead of sitting in the gut as a mineral salt waiting to dissolve, it travels in along the amino-acid route.

Two practical consequences. More of what you take actually reaches you. And it’s far gentler on the stomach, because it isn’t hanging around in the gut pulling water in after it.

The glycine isn’t just a delivery vehicle either. It’s the simplest amino acid there is, and the body uses it for plenty of its own purposes once the magnesium is unloaded.

The release

Your body can’t
save it for later.

Magnesium isn’t stockpiled in any convenient way. What’s surplus in the moment gets filtered out by the kidneys and leaves. Take one large dose all at once and a share of it is gone within hours, whatever the label promised.

This capsule is built to release across 24 hours instead — so the supply arrives closer to the rate the body actually spends it. Through the working day. And through the night, when muscles and the nervous system do the bulk of their repair.

It also means timing is forgiving. Morning or evening, you’re covered either way.

What magnesium is authorised to say

Three functions.
No hand-waving.

These are the officially permitted health claims for magnesium. We’d rather print them exactly as written than invent something louder.

Fatigue reduction

Magnesium contributes to the reduction of tiredness and fatigue.

Muscle function

Magnesium contributes to normal muscle function.

Nervous system

Magnesium contributes to normal functioning of the nervous system.

Food supplements are not a substitute for a varied diet and a healthy lifestyle.

Before you buy any magnesium

Four things worth checking.
On any bottle, ours included.

Magnesium is one of the easiest supplements to make look impressive on a label. Here’s how to tell the difference in about ten seconds.

What to look for

A named form. Bisglycinate, citrate, malate. The form is the whole story with magnesium.
The elemental figure. How much actual magnesium is in there — not the weight of the compound carrying it.
A stated release profile. Immediate or extended. If it doesn’t say, assume it all arrives at once.
A dose you’d actually keep taking. One capsule a day survives a busy month. Four doesn’t.

What to be careful with

“Magnesium oxide” — or just “magnesium”. If the form isn’t named, there’s usually a reason.
A huge milligram number with no elemental figure. A big compound weight can carry a small amount of magnesium.
Three or four capsules to reach the front-of-pack dose. Check the serving size, not the headline.
Blends where magnesium is a garnish. Twelve ingredients usually means a token amount of each.

Run that list on our bottle too. It’s the reason this page spends more time on the form than on the price.

How to take it

One capsule.
That’s the whole protocol.

One a day

A single capsule covers the day. No splitting doses, no counting to four.

With water

With or without food — bisglycinate doesn’t need a meal to sit well.

Evening suits most

Most people settle on the evening. Morning works too — the 24h release makes timing forgiving.

What to expect

Minerals work on
mineral time.

Nobody should promise you a transformation by Friday. Here’s the honest shape of it.

Days 1–7

Mostly nothing

You’re topping up a store, not taking a stimulant. The main thing to notice this week is what doesn’t happen — no stomach complaints.

Weeks 2–3

The edges soften

This is usually where people first mention evenings feeling calmer, or falling asleep taking less effort than it did.

Weeks 4–6

The afternoon changes

The clearest reports land here — the mid-afternoon drop stops being a fixed appointment, and night-time leg twitches get less frequent.

Ongoing

You stop noticing it

Which is the actual goal. A mineral doing its job is a mineral you never think about. Most people only notice again when they run out.

Individual experience varies. Magnesium supports normal function — it isn’t a treatment for any condition.

Let’s be straight about the downside

Worst case. Best case.

Worst case

You take it for a month, feel no clear difference, and tell us. We refund the bottle. You’re out the few minutes it took to order and nothing else — and you’ve ruled magnesium out properly, with a form that actually absorbs, instead of ruling it out on the evidence of a $9 bottle of oxide.

Best case

The 3pm wall stops being a fixed appointment. Your legs stop twitching the moment you lie down. Evenings wind down instead of grinding to a halt. And one capsule a day is so little to keep up that you’re still doing it a year from now — which is where the real benefit of a mineral lives.

Start with 3 bottles — $78.50

$26.16 per bottle · free US shipping · refund if it does nothing

Questions worth asking

The honest answers.

Last time I took magnesium it wrecked my stomach. Will this?

Almost certainly that was oxide, or citrate at a high dose. Both are known for it — poorly absorbed magnesium stays in the gut and draws water in, which produces exactly the effect you’re describing. Bisglycinate is the form people switch to for precisely this reason: it’s absorbed along the amino-acid pathway rather than sitting in the gut as a salt. We can’t promise your body will agree, but if it doesn’t, we refund it.

Why is this more than the magnesium on Amazon?

Because the number on the front of a bottle and the amount of magnesium that reaches you are two different things. Cheap magnesium is almost always oxide, and the headline milligrams usually describe the weight of the whole compound rather than the magnesium inside it. We’d rather sell you one capsule a day of a well-absorbed form than three capsules a day of something that mostly leaves. On cost per bottle, we lose — openly. On cost per milligram that actually gets absorbed, the comparison looks different. Buy the cheap one first if you’d rather see for yourself; plenty of our customers did.

Morning or night?

Whichever you’ll actually remember. Most people land on the evening, because the glycine half of the molecule suits winding down and because it’s an easy habit to anchor to brushing your teeth. But the 24-hour release means you’re covered either way — this is one of the few magnesium products where the clock genuinely doesn’t matter much.

Can I take it alongside my other supplements?

Generally yes — magnesium sits comfortably with most things, and the extended release reduces the usual concern about a large dose competing with other minerals for absorption at the same moment. The standard exceptions apply: if you take prescription medication, particularly certain antibiotics, thyroid medication or anything for blood pressure, space them a couple of hours apart and check with your doctor or pharmacist. If you’re pregnant, breastfeeding or have reduced kidney function, speak to them before starting.

How long does one bottle last?

Thirty days exactly — 30 capsules, one a day. That’s why the three-bottle option is the one most people take: ninety days is roughly the window where you can judge whether a mineral is doing anything for you, and buying it in one go is about a quarter cheaper than buying it three times.

What happens if I stop?

Nothing dramatic. There’s no dependency and no rebound — you simply drift back toward whatever your diet alone provides. Magnesium is a topping-up exercise rather than a course you complete, which is the honest reason most people stay on it rather than cycling off.

Start with the form
that actually arrives.

One capsule a day. Thirty days a bottle. Released across twenty-four hours instead of all at once.