Independent · evidence-based · 2026

Glycinate or Citrate?

The magnesium-form decision, settled in one page.

Both are well-absorbed organic salts. They differ in what they are bonded to, which changes what they do once they reach you. Glycinate calms. Citrate moves things through. Pick the one that solves your actual problem.

Take the 7-question quizCompare side by side
RDA women
310 to 320 mg
RDA men
400 to 420 mg
Supplement UL
350 mg
Magnesium · Mg-glycineGlycinate
Bonded toGlycine (amino acid)
Bioavailability25 to 35%
Elemental Mg~14% of compound
Start dose200 mg
Top dose400 mg
Price / dose$0.15 to $0.40
GI toleranceExcellent

Best signal

sleep · anxiety · stress

Magnesium · Mg-citrateCitrate
Bonded toCitric acid
Bioavailability25 to 35%
Elemental Mg~16% of compound
Start dose150 mg
Top dose400 mg
Price / dose$0.05 to $0.20
GI toleranceModerate (osmotic laxative)

Best signal

digestion · constipation · repletion

01 / Bioavailability

How much actually reaches your bloodstream

Bioavailability is the percentage of swallowed magnesium that gets absorbed. Both glycinate and citrate sit in the well-absorbed organic-salt band. Oxide is a different category entirely.

Read the full science
GlycinateAmino acid chelate
25 to 35%
CitrateOrganic salt
25 to 35%
MalateOrganic salt
20 to 30%
ThreonateCrosses blood-brain barrier
high
TaurateOrganic salt
good
OxideInorganic, poorly absorbed
4 to 5%

Bars scaled to 40% reference. Source: Lindberg 1990, Walker 2003, Schuette 1994, NIH ODS.

02 / Use case

Pick the form by what you actually need it for

Goal

Glycinate

Sleep

Glycine is itself sleep-promoting. Magnesium calms GABA. Citrate's laxative effect can wake you in the night.

Read more

Goal

Glycinate

Anxiety

GABA modulation plus glycine as an inhibitory neurotransmitter. The two-mechanism form for daily nerves.

Read more

Goal

Citrate

Constipation

Osmotic effect draws water into the gut. Most reliable supplement-strength laxative without prescription.

Read more

Goal

Either

Muscle cramps

It is the magnesium itself that supports muscle function. Glycinate if your stomach is sensitive, citrate if cheaper.

Read more

Goal

Glycinate

Pregnancy

Gentle on the stomach during a time GI is already unsettled. Citrate is acceptable if constipation is the concern.

Read more

Goal

Citrate

General repletion

Best price per elemental milligram from a well-absorbed form. Use to fill a 100 to 200 mg dietary gap.

Read more

03 / Chemistry

Same magnesium. Different bond. Different job.

The compound the magnesium is chelated to is what changes the experience. Glycine is a calming amino acid. Citric acid pulls water into the gut. Everything else, including how much elemental magnesium you actually get, follows from that.

Mg + glycine

Magnesium glycinate

  • + Bonded to glycine, an inhibitory neurotransmitter
  • + Glycine itself supports sleep and reduces night-time anxiety
  • + Gentlest GI profile of any magnesium form
  • + Slower, sustained release
  • - Roughly twice the price per dose
  • - Lower elemental percentage (~14%): bigger capsule for same dose
Mg + citric acid

Magnesium citrate

  • + Bonded to citric acid for high water solubility
  • + Mild osmotic laxative effect (good for constipation)
  • + Faster acting
  • + Cheapest well-absorbed form. Most pharmacies stock it.
  • - Loose stools at higher doses if you do not need a laxative
  • - No co-benefit beyond the magnesium itself

04 / Personalised pick

Which magnesium do you actually need?

Seven questions. Plain English. We will not try to sell you anything.

Question 1 of 70% complete

What is your primary goal for taking magnesium?

05 / Dosage

How much, when, with what

All numbers below are elemental magnesium, not capsule weight. A 500 mg glycinate capsule contains ~100 mg elemental.

Full dosage guide

Sleep

Glycinate

200 to 400 mg

elemental Mg / day

1 to 2 hours before bed

Anxiety

Glycinate

200 to 400 mg

elemental Mg / day

Split AM / PM

Constipation

Citrate

150 to 400 mg

elemental Mg / day

Morning with water

Cramps / general

Either

200 to 400 mg

elemental Mg / day

With meals

Read your label

Elemental magnesium content, not total capsule weight, is what counts. The number on the front of the bottle often is not what your body actually receives.

06 / All forms

There are more than two forms. Here are the rest.

Compare all 10+ forms
FormBioavailabilityGI tolerancePriceBest for
Glycinate25 to 35%Excellent$$Sleep, anxiety, sensitive stomach
Citrate25 to 35%Moderate$Constipation, repletion, value
Threonate (L-Threonate)HighGood$$$Cognition, memory, brain health
TaurateGoodGood$$Heart, blood pressure, calming
Malate20 to 30%Good$$Energy, fibromyalgia, muscle pain
Oxide4 to 5%Poor (laxative)$Budget laxative only
Chloride12 to 25%Variable$$Topical, oral repletion
Sulfate (Epsom)Topical onlyTopical only$Bath soaks. Not oral.

07 / Safety

When to be careful and when to talk to a doctor

Drug timing

Take 2 hours apart from

  • - Tetracycline / fluoroquinolone antibiotics
  • - Bisphosphonates
  • - Levothyroxine

Talk to your doctor first

If you take or have

  • - Diuretics or BP medication
  • - Reduced kidney function
  • - Heart rhythm conditions

Stop and seek care

Red-flag symptoms

  • - Severe diarrhoea or dehydration
  • - Irregular heartbeat or weakness
  • - Confusion or breathing changes
Full safety and interactions guide

08 / FAQ

People also ask

01Can I take both magnesium glycinate and citrate?
Yes. Many people take glycinate in the evening for sleep and relaxation, and citrate in the morning for digestive support and general magnesium repletion. Just keep your total daily elemental magnesium under 400 mg from supplements unless directed otherwise by a doctor.
02Will magnesium citrate make me go to the bathroom?
At higher doses, possibly. Citrate has a mild osmotic laxative effect that draws water into the intestines. Start with 100 to 200 mg of elemental magnesium and see how you respond before increasing the dose.
03How long until I feel the effects of magnesium?
Sleep and relaxation benefits from glycinate are often noticed within 1 to 2 weeks. Digestive benefits from citrate can be felt within days. Full magnesium repletion for deficiency takes 4 to 6 weeks of consistent supplementation.
04Can I take too much magnesium?
The tolerable upper intake level for magnesium from supplements is 350 mg per day of elemental magnesium (this does not include magnesium from food). Higher doses increase the risk of side effects like diarrhoea, nausea, and cramping. Excess is typically excreted by the kidneys in healthy individuals.
05Does magnesium help with leg cramps?
Research is mixed, but many people report benefit from magnesium supplementation for leg cramps. Either glycinate or citrate works for this purpose, as the magnesium itself (not the bonded compound) supports muscle function.
06Should I take magnesium with food?
Yes. Taking magnesium with food improves absorption and reduces the chance of GI side effects. This is especially important with citrate, which is more likely to cause digestive discomfort on an empty stomach.
07What is elemental magnesium and why does it matter?
Elemental magnesium is the actual amount of magnesium in a supplement, separate from whatever it is bonded to. A 500 mg magnesium glycinate capsule may only contain 100 mg of elemental magnesium. Always check the elemental magnesium content on the label to compare products accurately.
08Is magnesium glycinate worth the higher price?
If you are taking magnesium primarily for sleep, anxiety, or stress, yes. The glycine component adds its own calming and neuroprotective benefits on top of the magnesium. If you need magnesium for general health or constipation, citrate offers better value.
Not medical adviceThis site is informational. Always consult a doctor or pharmacist before starting any supplement, particularly during pregnancy, with chronic conditions, or alongside prescription medications.

Updated 2026-04-28