Best Magnesium Supplements, Scored on a Public Rubric
Magnesium is the most-searched supplement on Amazon, and for good reason: roughly 48% of US adults consume below the Recommended Dietary Allowance, according to the NIH Office of Dietary Supplements. Choosing a magnesium supplement is more complicated than picking a brand — form (glycinate, citrate, oxide, malate, threonate), elemental dose, and third-party testing all change what you actually get. This roundup scores seven widely-available Amazon products on our 6-metric rubric so you can see exactly why we rank them the way we do.
Top pick
Thorne — Basic Nutrients Magnesium Bisglycinate
135mg elemental magnesium bisglycinate, 60 capsules, NSF-certified facility
Doctor's Best — High Absorption Magnesium Glycinate/Malate
At a glance
Tap a column to sort| # | Best for | Price | ||
|---|---|---|---|---|
| 1 | | Overall pick | 8.7/10 | $52.00 |
| 2 | | Best value for glycinate at scale | 8.2/10 | $23.99 |
| 3 |  | Budget choice with third-party testing | 7.8/10 | $12.24$14.19 |
| 4 |  | Best drink-powder option | 7.2/10 | $49.00 |
| 5 |  | L-threonate form | 7.7/10 | $28.32$31.50 |
| 6 |  | Simple | 7.7/10 | $14.95 |
| 7 |  | Blended-form option for people unsure which form | 7.2/10 | $38.95 |
Prices pulled from Amazon as of Jul 6, 2026 and are subject to change. The price shown on Amazon at checkout applies.
How we scored
Every product below is scored on six metrics, 0-10 each, with the weighting described on how we review. The criteria specific to this category:
- Chelated or organic forms (glycinate, citrate, malate) prioritized over oxide, which has roughly 4% absorption in published studies.
- Elemental magnesium disclosed on the label — not just mg of the compound.
- Third-party testing evidence (USP, NSF, Informed Sport, or published certificate of analysis).
- Filler and additive disclosure — no undisclosed proprietary blends.
- Price per gram of elemental magnesium, not price per bottle.
- Brand transparency about sourcing, testing, and contamination results.
What to know before buying
- Target 200-400 mg elemental magnesium per day from supplements, combined with dietary sources. Anyone with kidney disease should consult a doctor before supplementing.
- Glycinate is the most-studied form for low gastrointestinal side effects. Citrate is effective and inexpensive but has a laxative effect at higher doses. Oxide is cheap but poorly absorbed.
- Gummies rarely disclose elemental dose clearly and often contain 2-4g of sugar per serving — not a good value for mineral supplementation.
Our picks
Thorne — Basic Nutrients Magnesium Bisglycinate
Key specs: 135mg elemental magnesium bisglycinate, 60 capsules, NSF-certified facility
$52.00Check price on AmazonPros
- NSF Certified for Sport — one of the highest third-party testing bars
- Fully-chelated bisglycinate, well-tolerated at recommended dose
- Label discloses elemental mg and compound mg separately
- Published heavy-metal testing summaries on brand site
Cons
- Premium price per elemental gram
- Smaller per-capsule dose means multiple capsules for 300-400mg target
Thorne — Basic Nutrients Magnesium Bisglycinate
- Third-party testing10/10
- Bioavailability9/10
- Clinical evidence8/10
- Value6/10
- Brand transparency10/10
- Form & absorption9/10
Doctor's Best — High Absorption Magnesium Glycinate/Malate
Key specs: 100mg elemental magnesium, 240 tablets, chelated form (TRAACS)
$23.99Check price on AmazonPros
- TRAACS chelate is a named, researched patent — not generic
- Inexpensive per elemental gram
- USP-verified certificate available on manufacturer site
- High capsule count per bottle — cost-effective for daily use
Cons
- Capsule size is large and some users find it hard to swallow
- Contains stearic acid as a binding agent (disclosed)
Doctor's Best — High Absorption Magnesium Glycinate/Malate
- Third-party testing8/10
- Bioavailability8/10
- Clinical evidence7/10
- Value10/10
- Brand transparency8/10
- Form & absorption8/10
NOW Foods — Magnesium Citrate
Key specs: 200mg elemental magnesium citrate, 250 tablets, USP-verified
$12.24$14.1914% offCheck price on AmazonPros
- NOW maintains an in-house ISO-certified analytical lab and publishes COAs
- Very affordable per elemental gram
- Widely available with consistent batch quality
Cons
- Citrate can have a mild laxative effect at doses above 400mg
- Tablets are coated with vegetable glaze — not an issue but less clean than capsule-only
NOW Foods — Magnesium Citrate
- Third-party testing8/10
- Bioavailability7/10
- Clinical evidence7/10
- Value10/10
- Brand transparency8/10
- Form & absorption7/10
Moon Juice — Magnesi-Om
Key specs: 311mg elemental magnesium (gluconate + citrate + L-threonate), 28 servings
$49.00Check price on AmazonPros
- Combines three forms including L-threonate, which crosses the blood-brain barrier
- Berry powder format is a nicer evening routine than capsules for many people
- Clear elemental-dose labeling
Cons
- Significantly more expensive per elemental gram than capsule options
- Less extensive public third-party testing data compared to Thorne or NOW
Moon Juice — Magnesi-Om
- Third-party testing6/10
- Bioavailability9/10
- Clinical evidence7/10
- Value5/10
- Brand transparency7/10
- Form & absorption9/10
Life Extension — Magtein Magnesium L-Threonate
Key specs: 2,000mg of Magtein (144mg elemental magnesium), 90 capsules
$28.32$31.5010% offCheck price on AmazonPros
- Magtein is the patented L-threonate form used in the original published studies
- Life Extension publishes batch testing data
- Targeted to a specific use case — cognition research literature
Cons
- Expensive per elemental gram compared to glycinate
- Low elemental dose per serving — would need to stack with another form for general repletion
Life Extension — Magtein Magnesium L-Threonate
- Third-party testing8/10
- Bioavailability8/10
- Clinical evidence8/10
- Value5/10
- Brand transparency9/10
- Form & absorption8/10
Nutricost — Magnesium Glycinate
Key specs: 420mg elemental magnesium per 2-cap serving, 240 capsules, Informed-Sport-tested line
$14.95Check price on AmazonPros
- Label clearly breaks down elemental vs compound mg
- Informed-Sport certification on selected batches
- Cost-effective per elemental gram
Cons
- Third-party testing coverage is batch-selective, not all-batch
- Larger dose per serving may cause GI effects in sensitive users — split the dose
Nutricost — Magnesium Glycinate
- Third-party testing7/10
- Bioavailability8/10
- Clinical evidence7/10
- Value9/10
- Brand transparency7/10
- Form & absorption8/10
Nested Naturals — Triple Magnesium Complex
Key specs: 300mg elemental magnesium (glycinate + malate + citrate), 180 capsules
$38.95Check price on AmazonPros
- Combines three well-absorbed forms in a single capsule
- Non-GMO Project Verified and Informed Sport on published batches
- Moderate per-elemental-gram cost
Cons
- Doesn't break down how much comes from each form on the label
- Blended formulas make it harder to attribute GI effects if they occur
Nested Naturals — Triple Magnesium Complex
- Third-party testing7/10
- Bioavailability8/10
- Clinical evidence7/10
- Value7/10
- Brand transparency6/10
- Form & absorption8/10
Frequently asked questions
It depends on the goal. Magnesium glycinate is the most-studied form for low GI side effects and general daily repletion. Citrate is effective and cheap but can have a laxative effect. L-threonate is specifically researched for crossing the blood-brain barrier. Oxide is inexpensive but has poor absorption (around 4% in published data) and is not recommended for supplementation.
Related reading
Sources
- Magnesium — Fact Sheet for Health Professionals — NIH Office of Dietary Supplements, 2022
- Bioavailability of US Commercial Magnesium Preparations — Magnesium Research, 2001
- The Effect of Magnesium Supplementation on Primary Insomnia in Elderly — Journal of Research in Medical Sciences, 2012
- USP Dietary Supplement Verification — US Pharmacopeia
Last verified: April 21, 2026. See our editorial policy and how we review for details on scoring and update cadence. Canonical URL: https://trustedhealthgear.com/reviews/best-magnesium-supplement.
Thorne — Basic Nutrients Magnesium Bisglycinate
$52.00 · on Amazon