Supplement Comparison

Magnesium Glycinate vs Oxide: Which Form Actually Absorbs?

Take glycinate for daily magnesium, sleep and calm: it's well absorbed and gentle on the stomach. Magnesium oxide is the cheapest form but poorly absorbed; most of it passes through and acts as a laxative. Oxide is fine for occasional constipation but a weak choice for correcting a deficiency.

The verdict on Magnesium overall

Strong consensus for

Magnesium supplements are worth taking.

8 sources: 6 positive, 2 partly

8 sources: 6 positive, 2 partly

Based on what researchers say in publicly available videos, not medical advice. Always consult your healthcare provider before starting, stopping, or changing any supplement.

What the evidence says about the form

Each claim gets one verdict, worked out from every counted mention. One dot is one source: a researcher or a study. Tap a dot to see its receipt.

positive partly neutral negative Each researcher and each study counts once per claim, however often they come up.

  1. Not enough evidence

    Magnesium glycinate and malate are better absorbed than other forms of magnesium.

    2 sources: 1 positive, 1 partly. Fewer than 3 sources so far.

    Researchers say

    1 positive, 1 partly

    Studies show

    No study counted yet.

    6 more not counted · see why
    We could not confirm who is speaking. 2
    We could not tell where the evidence comes from. 2
    The study cited could not be identified. 1
    A host's remark inside an interview. 1
    Show the receipts from 2 sources
    1. Rhonda Patrick, on The Dr. Hyman Show, at 1:16:02 Video · positive · Opinion

      “magnesium malate magnesium um glycinate and citrate if you're constipated right so so those so those are the organic salts which are more bioavailable”

    2. Mark Hyman Video · partly · 2 mentions

      on The Dr. Hyman Show, at 08:57 · partly · Opinion

      “but it's not absorbed well so you want to get chelated magnesium you want to get magnesium glycinate or citrate”

      on The Dr. Hyman Show, at 09:06 · partly · Opinion

      “it's not absorbed well so you want to get chelated magnesium you want to get magnesium glycinate or citrate”

  2. Leaning for

    Magnesium glycinate or malate is the best form for daily magnesium needs.

    3 sources: 3 partly.

    Researchers say

    3 partly

    Studies show

    No study counted yet.

    7 more not counted · see why
    We could not tell what position it takes on this claim. 3
    We could not confirm who is speaking. 2
    The study cited could not be identified. 1
    A host's remark inside an interview. 1
    Show the receipts from 3 sources
    1. Dr Michael Breus, on Rangan Chatterjee's channel, at 1:28:48 Video · partly · Opinion

      “So, I start most people on magnesium glycinate um with about 150 to 200 milligrams.”

    2. Mark Hyman Video · partly · 3 mentions

      on The Dr. Hyman Show, at 08:59 · partly · Opinion

      “you want to get chelated magnesium you want to get magnesium glycinate or citrate if you tend to be more”

      on The Dr. Hyman Show, at 27:47 · partly · Opinion

      “magnesium glycinate or magnesium 38 which is some the form that crosses the bloodb brain barrier helps reduce anxiety”

      on The Dr. Hyman Show, at 09:30 · partly · Opinion

      “if you take too much magnesium citrate you'll get diarrhea so you want to use magnesium glycinate”

    3. Dr. Rhonda Patrick Video · partly · 2 mentions

      on Huberman Lab, at 21:11 · partly · Opinion

      “I would say malite would be the best. That has to do with the short chain fatty acids being good for the gut.”

      on FoundMyFitness, at 23:09 · neutral · Opinion

      “taking a supplement magnesium glycinate citrate malate are”

Where the sources disagree

Built from every credited researcher and cited study on each claim.

Strong consensus for

Magnesium supplements are worth taking.

Supports it 6 sources
Partly 2 sources
Not enough evidence

Magnesium glycinate and malate are better absorbed than other forms of magnesium.

Supports it 1 source
Partly 1 source

Precis is not affiliated with or endorsed by YouTube or by any researcher, show or publisher we quote. We take no sponsorship, ad or affiliate money, and every verdict is our own review of what was said. How we stay independent

Key Differences

Absorption

Magnesium Glycinate

Well-absorbed — chelated to glycine

Magnesium Oxide

Poorly absorbed: much of it passes through the gut

Best For

Magnesium Glycinate

Daily needs, sleep, calm/anxiety, muscle relaxation

Magnesium Oxide

Occasional constipation — its laxative pull is the main use

GI / Bowel Effect

Magnesium Glycinate

Gentle, well tolerated

Magnesium Oxide

Strong laxative, grouped with the forms that loosen the bowel

Usable (Elemental) Magnesium

Magnesium Glycinate

Good — most of the dose is actually absorbed

Magnesium Oxide

High on the label, but low absorbed = little usable magnesium

Cost

Magnesium Glycinate

Affordable

Magnesium Oxide

Cheapest form — common in budget/drugstore products

What the sources say

Magnesium Glycinate

Named as a well-absorbed daily form

Magnesium Oxide

Called poorly absorbed; taken by some for its bowel effect

Bottom Line

If your goal is to raise your magnesium (for sleep, calm or a deficiency), glycinate wins easily: it's well absorbed and gentle. Magnesium oxide is the form in the cheapest drugstore tablets, and its defining trait is poor absorption. Much of it never gets into your body. Instead it pulls water into the bowel, which is why it works as a laxative (milk of magnesia is magnesium hydroxide, a close cousin). The only real reason to choose oxide is if you want the cheap laxative effect. For everything else (daily needs, sleep, muscle relaxation), use glycinate.

Protocol notes — Magnesium

Dosage
300-500mg of elemental magnesium daily (Peter Attia: 300-500mg; Rhonda Patrick: ~400mg; Mark Hyman: 400mg+).
Form
Glycinate or malate for everyday absorption (Rhonda Patrick). Carbonate for full absorption without gut effects (Peter Attia). Threonate for the brain only; don't count it toward daily needs. Citrate or oxide if you want a looser bowel.
Timing
Smaller doses spread across the day absorb better. Carbonate in the morning (Peter Attia). An evening dose for sleep.
Notes
Standard blood tests for magnesium are unreliable: the body holds plasma levels steady by drawing from bone, which hides a deficiency (Peter Attia; Rhonda Patrick). Too much supplemental zinc can block magnesium absorption. Physically active adults need 10-20% more than the sedentary RDA.

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