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Klean Athlete Klean Magnesium (120 mg, 90 capsules)

Reader ratings
Klean Athlete Klean Magnesium (120 mg, 90 capsules)

Magnesium glycinate, 120 mg a capsule, in a plant capsule with a trace of ascorbyl palmitate. NSF lists 13 lots, but no tester has published its metals. About $0.29 a day at one capsule, the cheapest per milligram of the magnesium we list.

Best for People who want a gentle glycinate magnesium at a low price and an NSF listing, and who will check the seller before buying.

Our rating
Fair (3.4 of 5)
Price range
Budget
Verified marks
NSF Certified for Sport (listing 1572352, Klean Magnesium, 90 capsules, 13 lots)
Size
90 vegetarian capsules, 120 mg of magnesium each (90 servings at one a day; the directions allow 1 to 4 capsules a day)
Made in
Not stated.

approx. $27 for 90 capsules

See it on Klean Athlete’s site → (opens in a new tab)

We are not affiliated with Klean Athlete. This link goes to the maker’s own page, with no tracking code. How we're funded.

Also sold at Amazon ($27), Blue Sky Vitamin ($27), Natural Health Co ($27) .

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    Reviews are personal experiences, not research, and they never change our quality ratings. Every review is read by our team before it appears.

    How we evaluated it

    How it scores Our rating, metric by metric Fair, 3.4 of 5
    1. Ingredients 25% of the rating 4 of 5

      Magnesium glycinate at 120 mg in a plant capsule, with only ascorbyl palmitate added; nothing artificial and no blend.

    2. Independent testing 35% of the rating 3 of 5

      NSF lists 13 lots, which the maker pays for and which shows no results; no outside lab has published lead or other metals for it.

    3. Evidence 15% of the rating 3 of 5

      Glycinate at 120 mg a capsule is a sensible form and dose, but the directions allow up to four capsules (480 mg), over the 350 mg limit, and our review finds only small, mixed trials for magnesium and sleep.

    4. Trust 10% of the rating 3 of 5

      No recall or warning letter found, but two California lead notices (2025, 2026) name another Klean product, its pre-workout.

    5. Value 15% of the rating 4 of 5

      About $0.29 a day at one capsule, $0.25 per 100 mg of magnesium, below the other magnesium products we list.

    The rating, 3.4 of 5, is the weighted average of these scores. See how we rank vitamins & minerals and our standard.

    Where to buy Stores and the prices we saw 3 stores

    Prices as we saw them on November 3, 2026. They change often. These links carry no tracking code and earn us nothing.

    What’s in it Every ingredient, in label order 3 ingredients
    1. Magnesium (as magnesium glycinate), 120 mg
    2. Hydroxypropyl methylcellulose (vegetarian capsule)
    3. Ascorbyl palmitate
    Who tested it What each test found, and who paid for it 1 test
    • Paid certification NSF (Certified for Sport; the maker pays)

      Lists “Klean Magnesium” (listing 1572352): capsule, 90 count, one capsule a serving, 13 lots (50343771, 50363061, 50353242, 50337886, 50338884, 50343522, 50359713, 50337095, 50359712, 50368012, 50354492, 50332637 and 50356377). NSF says the program checks label accuracy, contaminants, banned substances and the factory. It publishes lots, not results. Open ↗ (opens in a new tab)

    Who paid, and why it matters
    • Independent The tester took no money from the maker for it: a consumer group, a journalist, a university or a regulator.
    • Paid certification An outside lab or certifier tested or listed it, and the maker paid for that.
    • Maker’s own test A lab report or certificate of analysis the maker commissioned and published.

    A certification is a floor, not a verdict: it checks what its program checks and nothing else. We weigh tests by someone with no stake in the result most.

    What people ask Worries raised online and elsewhere, and what we found 5 questions
    Has Klean Athlete had lead problems?
    Not with this product, but with another. California’s Attorney General lists two 60-day notices alleging lead in Klean Athlete’s Pre-Workout in Natural Lemon Tea Flavor (2025-03738, filed September 2025, and 2026-00635, filed February 2026), which also name Pure Encapsulations, LLC, Target Corporation and Pattern Inc. as alleged violators. Neither names magnesium (search (opens in a new tab)). FDA’s enforcement databases list no Klean Athlete recall, and its warning-letter search finds none (searched 2026-11-03).
    Does an NSF Certified for Sport listing mean it is pure?
    It means NSF checked this product, and says (opens in a new tab) it verifies the contents match the label and that contaminants are not at unsafe levels. The listing shows lot numbers, not the metal results, so you cannot read a lead number. See how to tell if a supplement is pure.
    Is it really sold by Klean Athlete on Amazon?
    No. The listing’s seller is Pattern, a third party that is also named in the 2026 lead notice above, as it is beside many other brands in California notices. The product is the same 90-capsule bottle at the maker’s price, but check the seller line, or buy from a specialty shop we link.
    How many capsules is it safe to take?
    The directions on Amazon’s and Natural Health Co’s listings say to take 1 capsule, 1 to 4 times daily, or as a trainer, coach or health professional directs. One capsule is 120 mg. Four is 480 mg, above the 350 mg upper limit for supplemental magnesium that our types guide cites. Start with one and ask a clinician before going higher.
    Will magnesium glycinate help me sleep or cramp less?
    Maybe a little. Our sleep and stress review describes small trials with mixed results, and the types guide says form-specific benefits are not proven. The maker’s own copy is about energy, muscle contraction and recovery, not sleep.
    Why we chose it What put it on our list 4 points
    • The label is short: magnesium as magnesium glycinate (120 mg, 29% of the daily value) in a hydroxypropyl methylcellulose capsule, with ascorbyl palmitate. No sweetener, flavor, color or proprietary blend.
    • Glycinate is the form our guide to the types of magnesium calls gentlest on the stomach. One capsule, 120 mg, sits well under the 350 mg upper limit for supplemental magnesium, though the label’s directions run to four capsules a day (see below).
    • NSF’s Certified for Sport database lists Klean Magnesium in 90-capsule bottles with 13 lots. NSF says its program checks that the contents match the label, that there are no unsafe levels of contaminants and that none of 290 banned substances are present.
    • At $26.50 for 90 capsules it costs about $0.29 a day at one capsule, or $0.25 per 100 mg of magnesium, less than Momentous’s capsule ($0.28 per 100 mg) and Thorne’s powder ($0.43).
    Trade-offs What to weigh before you buy 5 points
    • NSF publishes lot numbers, not results, and the maker pays for the program. We found no outside lab result for lead or other metals in this product.
    • The maker’s page asks you to log in to add to cart, and on Amazon the seller is Pattern, a third party. Klean’s pre-workout has drawn two lead notices (see below).
    • The directions say to take 1 capsule, 1 to 4 times daily, or as a trainer, coach or health professional directs. Four capsules is 480 mg of magnesium, above the 350 mg upper limit for supplemental magnesium, so keep to what a clinician advises.
    • Magnesium for sleep and stress has modest support: our review describes small trials and mixed results.
    • Ask a clinician first if you have kidney disease, which makes it harder to clear magnesium.
    What to know Details worth knowing first

    Klean Magnesium is a plain magnesium glycinate capsule: 120 mg of magnesium, a plant capsule and a trace of ascorbyl palmitate. Our guide to the types of magnesium explains why glycinate is the form people choose when other kinds upset the stomach, and magnesium, sleep and stress covers what the research shows.

    It is here for the label and the NSF listing. NSF’s Certified for Sport database lists the 90-capsule bottle with 13 lots, so someone outside the factory has checked the contents against the label. The listing shows lots, not results, and Klean pays for it, so we could not read a lead number. For the limits of a listing, see how to tell if a supplement is pure.

    Two cautions. Klean’s pre-workout drew California lead notices in 2025 and 2026, not this product, but it is part of the record. And the maker’s page asks for a login, while the Amazon seller is a third party, so buy from a specialty shop or check the seller line. At about $0.29 a day for one capsule it is the cheapest magnesium we list, but the directions allow up to four capsules a day, which is more than the 350 mg limit for supplemental magnesium, so start with one.

    What we checked Each claim, and how sure we are of it 6 checks
    Third-party tested
    Yes
    Tested by
    NSF (Certified for Sport, paid by the maker)
    How Klean Athlete Klean Magnesium (120 mg, 90 capsules) measures up against our vitamins & minerals criteria
    What we checked What we found
    Third-party tested Verified NSF’s Certified for Sport database lists the product with 13 lots (opened 2026-11-02). The maker pays for NSF. SuppCo, a testing app, lists it with a TrustScore of 9.3 but says it has not verified product-specific testing.
    A certificate of analysis Not verified None on the maker’s page, and we found no lot report. NSF shows lots only.
    The right form Verified Magnesium glycinate, 120 mg elemental magnesium per capsule, read from the label NSF holds for the listing.
    A plain label Verified One active, 120 mg of magnesium as glycinate, in a hypromellose capsule with ascorbyl palmitate. No proprietary blend. Directions: 1 capsule, 1 to 4 times daily.
    Disclosed extras Maker’s claim Other ingredients: hydroxypropyl methylcellulose (vegetarian capsule) and ascorbyl palmitate, an antioxidant. The maker lists it as gluten free, GMO free, vegan and vegetarian.
    Prop 65 notices and recalls Verified Two 2025 and 2026 lead notices on Klean Athlete’s pre-workout, none on magnesium; no FDA recall or warning letter found for Klean Athlete (searched 2026-11-03).
    What the labels mean
    • Verified We opened an independent record that confirms it: a certifier’s listing, a regulator’s list or a lab report. It is linked under Sources.
    • Maker’s claim The maker says so on its own page or label. We read it but found no independent record.
    • Not verified We looked and could not confirm it, or the maker does not say. Treat it as unknown.
    Sources Where our facts come from 11 sources
    1. Klean Athlete: Klean Magnesium product page. Maker’s page. $26.50, 90 capsules, 120 mg of magnesium glycinate; “log in to add to cart”. Seen 2026-11-02. Open ↗ (opens in a new tab)
    2. NSF Certified for Sport listing: Klean Magnesium. Certifier or regulator listing. Capsule, 90 count, 13 lots, United States. Open ↗ (opens in a new tab)
    3. NSF label image for the listing (supplement facts). Certifier or regulator listing. Magnesium 120 mg (as magnesium glycinate); other ingredients hydroxypropyl methylcellulose and ascorbyl palmitate. Open ↗ (opens in a new tab)
    4. NSF Certified for Sport: what the mark means. Certifier or regulator listing. 290 banned substances, label match, unsafe contaminants, GMP facility. Open ↗ (opens in a new tab)
    5. SuppCo: Klean Athlete Klean Magnesium. Independent source. TrustScore 9.25 (shown as 9.3); says product-specific testing is not currently verified. Open ↗ (opens in a new tab)
    6. California Attorney General Prop 65 60-day notice search: Klean Athlete. Certifier or regulator listing. Notices 2025-03738 and 2026-00635 (lead, Pre-Workout Natural Lemon Tea Flavor). Checked 2026-11-03. Open ↗ (opens in a new tab)
    7. openFDA food and drug enforcement searches for Klean Athlete. Certifier or regulator listing. No matches in the food or drug databases on 2026-11-03. Open ↗ (opens in a new tab)
    8. FDA warning letters database. Certifier or regulator listing. Searched by company name on 2026-11-03: no letter for Klean Athlete. Open ↗ (opens in a new tab)
    9. Amazon listing: Klean Athlete Klean Magnesium, 90 capsules. Independent source. $26.50, seller Pattern, shipped by Amazon, in stock on 2026-11-03. Directions: 1 capsule, 1-4 times daily. Open ↗ (opens in a new tab)
    10. Blue Sky Vitamin listing: Klean Magnesium 90 capsules. Independent source. $26.50, in stock on 2026-11-03. Open ↗ (opens in a new tab)
    11. Natural Health Co listing: Klean Magnesium, 90 veg capsules. Independent source. $26.99, in stock on 2026-11-03. Gives the same directions and says NSF Certified for Sport. Open ↗ (opens in a new tab)
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