Guide
How much magnesium glycinate should you take a day?
The IOM's 1997 dietary reference intakes set the numbers most labels are measured against: an RDA of 310-420 mg a day from food and supplements, and a 350 mg/day limit on supplemental magnesium alone.
Electric Tiger Magnesium Glycinate provides 275 mg of elemental magnesium per three-capsule serving. That sits inside the Institute of Medicine's 1997 dietary reference intakes: the adult RDA runs 310-420 mg a day from food and supplements combined, and supplemental magnesium alone has a 350 mg/day upper limit, set at the dose where loose stools become more likely.
Where the numbers come from
The Institute of Medicine's 1997 dietary reference intake report is still the standing US reference for magnesium. It sets two different numbers, and mixing them up is the most common label-reading mistake:
| Group | RDA (food + supplements) | UL (supplements only) |
|---|---|---|
| Men, 19-30 | 400 mg/day | 350 mg/day |
| Men, 31+ | 420 mg/day | 350 mg/day |
| Women, 19-30 | 310 mg/day | 350 mg/day |
| Women, 31+ | 320 mg/day | 350 mg/day |
The RDA is a target for total intake, food included, and most people get a meaningful share of it from diet before a supplement enters the picture. The 350 mg upper limit is narrower: it applies only to magnesium taken as a supplement, and the ceiling exists because diarrhea, not any more serious effect, is what shows up first as the dose rises.
What that ceiling is actually based on
A 2023 review searched for every study published between 1997 and 2022 that tested a single-ingredient magnesium product and reported diarrhea as a specific outcome. Of ten studies found, seven — spanning 128 to 1,200 mg a day — reported no significant difference in diarrhea between the magnesium group and the control group. A search of the FDA's adverse event database turned up only 40 attributable gastrointestinal cases tied to single-ingredient magnesium products, and only about a third of those mentioned diarrhea specifically. The authors argue the current 350 mg limit may be conservative; it hasn't been changed.
What our label provides
Three capsules of Electric Tiger Magnesium Glycinate deliver 275 mg of elemental magnesium from 2,500 mg of magnesium glycinate, 30 servings a bottle, as low as $16.30 a bottle on subscription ($0.54 a serving). That's under both the top-end adult RDA (420 mg) and the 350 mg supplemental limit, which leaves room for magnesium you get from food without pushing your total past the ceiling that limit describes.
Splitting the dose, or taking it all at once
Our label directs three capsules once daily. Research on other magnesium forms has tested both approaches — a 2003 trial gave 300 mg of elemental magnesium as a single daily dose and measured blood, urine and saliva at 24 hours and again after 60 days — but nothing establishes that splitting a 275 mg glycinate dose changes the outcome. If a dose sits with you better split across the day, there's no reason not to; see when to take magnesium glycinate for what the evidence does and doesn't say about timing.
When the number is different for you
- Kidney disease: magnesium is cleared by the kidneys, and impaired clearance changes how a given dose behaves in the body, so ask your doctor before adding a magnesium supplement if you have kidney disease.
- Pregnancy or breastfeeding: magnesium needs shift in pregnancy and lactation, so ask your doctor for a number specific to your situation instead of using a general adult figure.
- Other supplements or medications. If you're already taking a multivitamin, an antacid, or a prescription medication, the amounts can add up or interact. See magnesium glycinate and medications: what to check.
Questions people ask
How much magnesium glycinate should I take a day?
Our label directs three capsules a day, providing 275 mg of elemental magnesium — under the 350 mg/day upper limit set for supplemental magnesium and within the adult RDA range of 310-420 mg a day from food and supplements combined.
Is there a different amount for women?
The IOM sets a slightly lower dietary RDA for women (310-320 mg/day) than for men (400-420 mg/day), reflecting average body size and intake patterns. The 350 mg/day supplemental limit doesn't differ by sex.
What if I take other magnesium supplements too?
Add up the elemental magnesium from every supplement source — not food — and compare the total to the 350 mg/day limit. A multivitamin, an antacid and a dedicated magnesium capsule can each contribute.
Is there a specific dose for sleep?
No dose of magnesium glycinate is established for sleep, and we don't make a sleep claim for this product. If that's what brought you here, magnesium glycinate and sleep: what the evidence actually shows covers the research directly.
What about kidney problems?
Talk to your doctor before starting any magnesium supplement. Reduced kidney function changes how magnesium is cleared, and the general adult dosing figures above assume normal kidney function.
Does taking more than the label mean better results?
Nothing in the research above suggests a dose above label directions does more for muscle, energy or nervous system function; it just moves you closer to the point where loose stools become more likely. Stick to label directions unless a doctor advises otherwise.
Sources
- Perspective: Call for Re-evaluation of the Tolerable Upper Intake Level for Magnesium Supplementation in Adults In 7 of 10 trials between 128 and 1,200 mg a day, magnesium caused no more diarrhea than the comparison.
- Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study In 46 healthy adults taking 300 mg a day for 60 days, citrate raised blood magnesium most; an amino-acid chelate did not beat it.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
