BUYING GUIDE33,000/month searches
47,000+ trials analyzed
59,000+ interactions
Not FDA evaluated

Before You Buy Magnesium

What to look for (and what to avoid)

TL;DR

Look for magnesium glycinate or citrate with 300-400mg elemental magnesium per serving. Avoid oxide (4% absorption). Check for "elemental" magnesium on the label, not just compound weight. Third-party tested is a plus.

Quick Checklist

Form is glycinate, citrate, or threonateMUST HAVE
300-400mg elemental magnesium per servingMUST HAVE
Third-party tested (USP, NSF, or ConsumerLab)IMPORTANT
No proprietary blends hiding amountsIMPORTANT
Reputable brand with transparent sourcingNICE TO HAVE

What to Look For

Red Flags (Avoid)
Magnesium oxide as main form

Only 4% bioavailable. Glorified laxative.

"Proprietary blend" on label

They're hiding how much actual magnesium is in there.

Claims "10 forms of magnesium!"

Marketing gimmick. You need ONE good form, well-dosed.

Mega-dose (600mg+ elemental)

More isn't better. Causes digestive issues.

No third-party testing

No way to verify what's actually in the bottle.

Green Flags (Look For)
Lists elemental magnesium amount

Transparency about actual dose.

Single or dual form (glycinate/citrate)

Focused, evidence-based formulation.

USP or NSF verified

Independent lab confirmed what's on the label.

Clean inactive ingredients

Less fillers = better product.

Forms Ranked

FormScoreBest ForNotes
Glycinate
10/10
Sleep, anxiety, general use80% bioavailable, calming glycine bonus
Citrate
8/10
Constipation, budget option25% bioavailable, well-studied
Threonate
8/10
Cognitive functionCrosses blood-brain barrier, expensive
Malate
7/10
Energy, muscle painGood for fibromyalgia
Taurate
7/10
Heart healthTaurine provides additional benefits
Oxide
2/10
Nothing (avoid)4% bioavailable, only good for constipation

Dosing Guide

Minimum200mg elemental
Optimal300-400mg elemental
Maximum400mg (RDA limit)
When to TakeEvening for sleep benefits, with food to reduce stomach upset
Pro TipSplit doses if taking 400mg+ to improve absorption

Is Magnesium For You?

You Might Need It If...

  • People with muscle cramps or restless legs
  • Those with sleep issues (glycinate specifically)
  • Anyone on a low-magnesium diet (processed foods)
  • People taking medications that deplete magnesium (PPIs, diuretics)
  • Athletes and heavy exercisers (lost through sweat)

You Probably Don't Need It If...

  • People with kidney disease (consult doctor first)
  • Those already eating magnesium-rich diet (leafy greens, nuts)
  • Anyone with low blood pressure (can lower it further)

Common Mistakes

Reality:

You absorb so little that you're actually paying MORE per absorbed mg.

The Bottom Line

Get magnesium glycinate if you want sleep/relaxation benefits, citrate if you need digestive help. Look for 300-400mg elemental per day. Skip anything with oxide as the main form. Third-party testing is worth the extra few dollars.

Learn More About Magnesium

More Buying Guides

About this information: Our analysis of Magnesium is based on peer-reviewed research from PubMed, ClinicalTrials.gov, and NIH databases. These statements have not been evaluated by the FDA. Supplements are not intended to diagnose, treat, cure, or prevent any disease.

Strong Evidence

Get Science-Backed Supplement Tips

Weekly insights from 47,000+ clinical trials

No spam. Unsubscribe anytime. We respect your inbox.

Check Your Current Magnesium

Already have magnesium? See how it stacks up.

Analyze My Stack