NOW Foods Magnesium Glycinate 200 mg Review

What NOW Magnesium Glycinate actually is

This is a single-ingredient mineral tablet, not a sleep formula.

The Supplement Facts panel on nowfoods.com (checked October 10, 2026) lists one active: 200 mg of elemental magnesium per two tablets, supplied as magnesium bisglycinate from Albion, the chelate supplier whose name appears on a lot of mineral labels.

Bisglycinate means each magnesium ion is bound to two molecules of the amino acid glycine. The commercial pitch is that the chelate is absorbed well and sits gently in the gut. We cover how much of that the independent evidence supports further down.

The rest of the label is excipients: citric acid, hydroxypropyl cellulose, vegetable stearic acid, silicon dioxide and a vegetarian coating built from hypromellose, sunflower lecithin, triethyl citrate and sunflower oil.

No added magnesium oxide is declared, which matters because some 'glycinate' products quietly use oxide to hit the headline number.

It comes in two sizes: 90 tablets (45 servings, SKU 1286) and 180 tablets (90 servings, SKU 1289).

The product is sold direct and through the usual retailers; this review grades it on the vendor's own documentation, the NIH magnesium fact sheet and the published trial evidence. We did not take it ourselves, and we will not pretend otherwise.

Who it is best for, and who should skip it

Magnesium supplements make the most sense for people who are probably not getting enough from food. NIH's fact sheet, citing NHANES 2013 to 2016 data, says 48% of Americans of all ages take in less magnesium from food and beverages than their Estimated Average Requirement.

That is a large gap for an unglamorous mineral.

This particular bottle suits:

• Adults eating few greens, legumes, nuts, seeds or whole grains who want a modest, labelled top-up.
• People who tried magnesium oxide and regretted it - the chelate form is widely reported to be easier on the gut, though the independent trial base for that is thin.
• Anyone who wants kosher, halal, vegan and non-GMO marks on one product - NOW lists all four.
• Cautious starters - 100 mg per tablet means you can begin at half a serving.
• Buyers who weight facility certification - Intertek GMP Supplement Certification is listed on the page.
• Should skip it: people with kidney disease or on dialysis, anyone on tetracycline or quinolone antibiotics or oral bisphosphonates who has not sorted out timing with a pharmacist, and anyone buying it as a stand-alone insomnia treatment.

What the label says about dose, and what NIH says about limits

The suggested use is two tablets, one to two times daily with food. One serving is 200 mg, which is 48% of the Daily Value. Two servings is 400 mg.

That second number deserves a pause. NIH's Office of Dietary Supplements sets the Tolerable Upper Intake Level for supplemental magnesium at 350 mg per day for adults.

The UL applies only to magnesium from supplements and medications, not from food, and the usual consequence of exceeding it is diarrhea, sometimes with nausea and cramping. The label's upper option sits 50 mg above that line.

For context, the adult RDAs NIH lists are 400 mg (men 19 to 30), 420 mg (men 31 and older), 310 mg (women 19 to 30) and 320 mg (women 31 and older).

Food covers part of that for everyone; a 200 mg supplement is designed to close a gap, not replace the diet.

Our reading: one serving a day with a meal is the conservative default. Going to two servings is a conversation to have with a clinician, especially if a multivitamin or an electrolyte mix such as LMNT is already adding magnesium to the day.

How the pricing works out per serving

On nowfoods.com, checked October 10, 2026, the 90-tablet bottle lists at $17.99 and showed a $13.49 sale price the same day; the 180-tablet bottle showed $23.99. Those are the vendor's figures. The per-serving math below is ours.

At list price the 90-count works out to about $0.40 per 200 mg serving, or $0.20 per 100 mg. The 180-count works out to about $0.27 per serving, or $0.13 per 100 mg.

The bigger bottle is the obvious buy if the product agrees with you.

Against the two other magnesium products we grade: Doctor's Best High Absorption Magnesium lists at $23.99 for 240 tablets, which is 120 servings of 200 mg, or about $0.20 per serving.

Natural Vitality Calm unflavored lists at $35.79 for 113 servings of 350 mg, about $0.32 per serving but only $0.09 per 100 mg because the dose is larger.

So NOW is priced in the middle: a few cents more per serving than Doctor's Best, less than the powder per serving but more per milligram. None of these numbers include shipping or retailer discounts, which move constantly.

Evidence: what magnesium does, and what it has not been shown to do

The nutritional case is solid. Magnesium is a cofactor in hundreds of enzyme systems, intake falls short for roughly half the population, and correcting a dietary shortfall with a modest supplement is uncontroversial. That is the claim this product can stand on.

The sleep case is weaker than the internet suggests. The best-known synthesis is a 2021 systematic review and meta-analysis by Mah and Pitre in BMC Complementary Medicine and Therapies. It found three randomized trials covering 151 older adults.

Pooled, magnesium shortened sleep onset by about 17 minutes versus placebo; total sleep time rose by about 16 minutes but did not reach statistical significance.

The authors rated every trial at moderate to high risk of bias and graded the evidence low to very low quality. Their conclusion was that the literature is too thin for clinicians to make confident recommendations, while noting magnesium is cheap and widely available.

That is roughly where we land: plausible, unproven, inexpensive to try with a clinician's blessing.

For a wider view of which supplements carry real evidence and which do not, our guide to supplements with the best evidence puts magnesium in context next to creatine and vitamin D.

Form and absorption: what NIH actually says about glycinate

Marketing for chelated magnesium leans on absorption. The NIH fact sheet is more measured. It states that the aspartate, citrate, lactate and chloride forms tend to have higher bioavailability than magnesium oxide and magnesium sulfate. Glycinate is not named in that sentence either way.

That does not mean glycinate absorbs poorly. It means the strongest independent statement on form does not specifically endorse it, and the gentleness reputation rests on manufacturer studies plus a very large volume of user reports. We treat that as a reasonable but unverified advantage.

In practice the decision between glycinate and citrate often comes down to the gut. Citrate, the form in Natural Vitality Calm, has a mild laxative effect at higher doses that some people want and others do not.

Glycinate is the form people usually move to when citrate is too active. Our magnesium guide by form and dose walks through oxide, citrate, glycinate, malate and threonate side by side.

Third-party testing and label seals

The product page lists Intertek GMP Supplement Certification. Intertek audits the facility against good manufacturing practice standards.

That is meaningful - it covers cleanliness, process controls and record-keeping - but it is not a product-level seal that verifies each batch of this tablet contains 200 mg of magnesium and nothing else.

The seals that do that job, NSF Certified, USP Verified and Informed Sport, do not appear on this product page as of October 10, 2026.

Our explainer on what third-party supplement seals actually verify spells out the difference, and it is worth reading before paying extra for any seal.

What the page does list: Kosher (Triangle K), Halal, Non-GMO, and Vegan or Vegetarian. The allergen statement is specific: not made with wheat, gluten, soy, milk, egg, fish, shellfish, tree nut or sesame ingredients, but produced in a facility that handles those allergens.

For a mineral tablet, that is above-average transparency.

For comparison, the Doctor's Best product page lists vegan, non-GMO, gluten-free and soy-free marks and no facility or product certification at all. On the paperwork, NOW is ahead.

Tolerability, interactions and the clinician conversation

Magnesium is not a free-for-all supplement. NIH's fact sheet lists several interactions worth knowing before the first tablet.

Tetracycline antibiotics such as doxycycline and quinolones such as ciprofloxacin can form insoluble complexes with magnesium. NIH's guidance is to take those antibiotics at least 2 hours before or 4 to 6 hours after a magnesium-containing supplement.

Oral bisphosphonates for bone density absorb less when taken near magnesium; a 2-hour separation is advised. Loop and thiazide diuretics increase urinary magnesium loss, while potassium-sparing diuretics reduce it, so the right dose depends on which one you take.

Long-term proton pump inhibitor use, typically beyond a year, can cause low magnesium, and the FDA advises checking serum levels in that situation.

Kidney disease changes the picture entirely because the kidneys clear excess magnesium.

None of this is medical advice; it is the list of reasons to talk to a clinician or pharmacist before adding this or any magnesium product, particularly alongside a multivitamin such as Ritual Essential for Women that already contains some.

Alternatives

Doctor's Best High Absorption Magnesium. Same 200 mg per two tablets, also an Albion chelate (lysinate glycinate), and a lower list price per serving on the 240-count bottle. Choose Doctor's Best if price per milligram is the deciding factor.

Choose NOW if facility certification, kosher or halal marks, or a more specific allergen statement matter to you. Our full Doctor's Best review has the detail.

Natural Vitality Calm (magnesium citrate powder). A fizzy drink mix at 325 to 350 mg per full serving that you can titrate by the teaspoon. Choose Calm if you dislike tablets or want a dose you can dial up from 1 g of powder.

Choose NOW if you want fixed, small dose steps and no laxative edge. See the Natural Vitality Calm review.

Food. Pumpkin seeds, almonds, spinach, black beans and whole grains cover a lot of the RDA for most people. If your diet already includes them daily, a supplement may be solving a problem you do not have.

The budget athlete's supplement stack is built on that principle.

Bottom line

NOW Foods Magnesium Glycinate is a competent, well-documented chelated magnesium at a fair price. The label is clean, the facility is GMP-certified, and the 100 mg tablet size suits cautious dosing.

Its weaknesses are shared with the whole category: no per-batch product seal, and sleep claims that the trials do not yet back.

Buy it to close a dietary gap, take one serving with food, keep the daily supplemental total at or under NIH's 350 mg ceiling unless a clinician says otherwise, and read the magnesium guide by form and dose if you are still deciding between glycinate and citrate.

Grades on this site reflect labels, pricing pages and published research, never affiliate payouts. Informational only, not medical advice.

Best for

Adults whose diet runs short on magnesium and who want a glycinate tablet with a facility certification, kosher and halal marks, and a conservative 100 mg per tablet.