Thorne Magnesium vs NOW Magnesium (2026 Comparison)
By Kazi Habib, B.Pharm, MBA, PMP · Updated May 19, 2026
Thorne Magnesium Bisglycinate wins on third-party certification (NSF Certified for Sport on the Magnesium Bisglycinate Powder SKU), single-form purity, and pharmaceutical-grade manufacturing standards. NOW Magnesium Glycinate wins on per-dose cost (about $0.18 vs Thorne's $0.66), wide retail availability (Whole Foods, Sprouts, iHerb, Amazon), and large per-bottle count (180 capsules vs Thorne's 60-90 servings). Both are real magnesium glycinate; both will produce the absorption advantages the Schuette 1994 trial documented in JPEN. The two brands compete in different price tiers and serve different buyer profiles.
TL;DR
- Thorne Magnesium Bisglycinate Powder: 200 mg elemental magnesium per scoop, NSF Certified for Sport, $0.66 per serving.
- NOW Magnesium Glycinate: 240 mg elemental magnesium per 3-tablet serving, $0.18-0.25 per serving (180 tablets = 60 servings).
- Both deliver real chelated magnesium at clinical dose ranges per the Schuette 1994 trial and Ates 2019 absorption profile.
- Thorne is NSF Certified for Sport on this SKU; NOW operates GMP-certified facilities but is not NSF Sport on this product.
- Halal: NOW carries selected halal-friendly products; Thorne similarly is vegetarian on selected SKUs. Neither is formally halal-certified for magnesium specifically.
- For Canadian readers: NOW is at every Whole Foods Canada and iHerb Canada at CAD ~$15-22 per 180-tablet bottle; Thorne ships from thorne.com Canada at CAD ~$45-55 per 60-serving tub.
Why trust this comparison
I am Kazi Habib, B.Pharm, MBA, PMP, with 10+ years across pharmaceutical sciences and life-sciences marketing. This comparison cross-references each brand's Supplement Facts panel against the Schuette 1994 magnesium bisglycinate bioavailability trial in JPEN, the Ates 2019 dose-dependent absorption study in Biological Trace Elements Research, and the NIH ODS Magnesium fact sheet. Both products purchased at full retail price.
Affiliate disclosure. Links pay FitFixLife a small commission if you buy. Medical disclaimer. Magnesium can interact with prescription medications (antibiotics, thyroid medications, bisphosphonates, diuretics). If you have kidney disease, take any of these medications, or are pregnant, consult your physician before starting daily magnesium supplementation.
Side-by-side ingredient comparison
| Specification | Thorne Bisglycinate Powder | NOW Magnesium Glycinate |
|---|---|---|
| Form | Magnesium bisglycinate | Magnesium glycinate |
| Elemental Mg per serving | 200 mg (1 scoop) | 240 mg (3 tablets) |
| Serving count | 60 scoops | 60 servings (180 tablets) |
| Other ingredients | Tapioca-based natural flavors | HPMC, stearic acid, silica, mag stearate |
| Third-party certification | NSF Certified for Sport | Not NSF Sport; GMP-certified facility |
| Cost per container | $40 (60-serving) | $11-15 (180 tablets) |
| Cost per serving | $0.66 | $0.18-0.25 |
| Cost per 100 mg elemental Mg | $0.33 | $0.08-0.10 |
Both products deliver chelated magnesium at clinical dose ranges. The active compound is essentially equivalent in absorption profile per the published bioavailability literature. The price difference reflects manufacturing standards, certification overhead, and brand positioning rather than meaningful difference in magnesium delivered.
Where Thorne wins
NSF Certified for Sport status on this SKU. Each batch is independently tested for banned substances per WADA criteria and for contaminants. For competitive athletes, this is the threshold differentiator. NOW Magnesium Glycinate is not NSF Sport certified.
Powder format flexibility. Thorne's powder allows users to titrate dose precisely (half-scoop for 100 mg, full scoop for 200 mg). Tablet form locks the dose at the per-tablet increment.
Pharmaceutical-grade manufacturing reputation. Thorne operates facilities meeting pharmaceutical industry standards including audits beyond the standard FDA cGMP requirement for dietary supplements.
Cleaner excipient profile. Thorne uses natural-flavor citrus-lime in the powder. NOW Magnesium Glycinate tablets include HPMC, stearic acid, silica, and magnesium stearate as standard tableting aids. All safe and inert but Thorne's powder avoids these.
Where NOW wins
Per-serving cost. $0.18-0.25 vs $0.66 = 62-73% cheaper per serving. Annual savings: NOW at $0.18 daily = $66/year; Thorne at $0.66 daily = $241/year. The $175 annual difference can fund other supplements.
Wide retail availability. Whole Foods, Sprouts, Vitamin Shoppe, iHerb, Amazon. Thorne is primarily Amazon, thorne.com direct, and pharmacist channels.
Higher elemental magnesium per serving. NOW delivers 240 mg vs Thorne's 200 mg. For users targeting 300-400 mg daily, one NOW serving plus dietary magnesium gets closer to the target.
Brand longevity. NOW Foods has operated since 1968. The brand has occasional ConsumerLab pass-through tests showing label accuracy.
Halal status and certification
Neither Thorne Magnesium Bisglycinate Powder nor NOW Magnesium Glycinate currently carries formal halal certification by JAKIM, MUI, IFANCA, HFA, or ESMA.
Thorne. Vegetarian, gluten-free, dairy-free. Tapioca-based flavor system. The glycine source for the bisglycinate compound is the unverified piece for halal-strict consumers; most pharmaceutical-grade glycine is produced via chemical synthesis (Strecker synthesis) rather than animal hydrolysis, but verifying with the brand is worthwhile.
NOW. Vegetarian (non-gelatin tablet binders). Vegetable capsule alternatives (HPMC) are used; no porcine gelatin in this SKU. Same glycine-source consideration as Thorne. NOW has several halal-friendly product SKUs in its catalog but does not specifically market Magnesium Glycinate as halal-certified.
Canadian availability and pricing
NOW in Canada. At every Whole Foods Canada, most Goodness Me natural-grocery stores, iHerb Canada, Amazon Canada, Vitasave. Pricing roughly CAD $15-22 per 180-tablet bottle = CAD $0.25-0.37 per serving. Cross-border availability is excellent.
Thorne in Canada. Primary channel is thorne.com with USD pricing plus shipping; Amazon Canada via third-party sellers. Landed Canadian cost roughly CAD $50-60 per 60-serving tub = CAD $0.83-1.00 per serving.
Canadian alternatives. AOR magnesium glycinate at CAD $25-30 for a 60-tablet bottle. Pure Encapsulations at CAD $35-45. CanPrev at CAD $30-40. All sit in the mid-tier between NOW and Thorne; all are Canadian-formulated.
Pharmacist take: elemental magnesium is the metric that matters
Glycinate vs bisglycinate is mostly labeling. Both describe the same chelate structure: one magnesium atom bonded with two glycine molecules. The Schuette 1994 trial documented absorption around 23.5% vs magnesium oxide's 22.8% overall, with notable advantages in patients with compromised intestinal function. From a reputable manufacturer, both terms describe the same compound.
Elemental magnesium is the dose number that matters. Magnesium glycinate is roughly 14% elemental magnesium by mass. A label showing 1,000 mg magnesium glycinate provides 140 mg elemental magnesium, not 1,000 mg. Both Thorne and NOW disclose elemental magnesium clearly (200 mg per scoop and 240 mg per 3-tablet serving respectively). Brands that bury elemental magnesium behind compound-weight numbers are the ones to avoid.
Magnesium oxide blending is the value-segment cheat code to avoid. Many cheap "magnesium" products blend magnesium oxide (4% bioavailable per Ates 2019) with a small amount of better forms. Both Thorne and NOW specifically avoid this; both are single-form chelate products. The premium over generic "magnesium complex" pills is justified by avoiding the oxide-blending issue.
Use cases: who picks what
- Pick Thorne if you are a competitive athlete needing NSF Certified for Sport; you value pharmaceutical-grade manufacturing; you want powder format flexibility for dose titration; you can pay $0.66/serving; you take magnesium for sleep at variable doses.
- Pick NOW if you want real magnesium glycinate at value pricing from an established manufacturer; you buy at Whole Foods or iHerb; you take a consistent daily dose; you are not subject to drug-testing; annual cost matters.
- Pick something else if you want magnesium L-threonate for cognitive support; magnesium citrate for occasional constipation relief; pharmacy-grade IV magnesium (clinical, prescriber-managed); or a halal-certified magnesium specifically (smaller specialty brands).
Dosing protocol and timing
Standard daily dose. 200-400 mg elemental magnesium daily for general adult use. The RDA is 320 mg for women and 420 mg for men; typical dietary intake covers 200-250 mg, leaving a supplemental gap of 100-200 mg.
Thorne dosing. 1 scoop (200 mg elemental Mg) in 8-10 oz cold water, ideally 30-60 minutes before bed for sleep-focused use.
NOW dosing. 3 tablets per serving (240 mg elemental Mg), or 1-2 tablets for users wanting lower dose. Take with water; can be with or without food.
Drug interactions worth flagging. Tetracycline antibiotics (doxycycline, minocycline) and fluoroquinolones (ciprofloxacin, levofloxacin): magnesium chelates the antibiotic in GI tract; space by 2-4 hours (4-6 for fluoroquinolones). Bisphosphonates (alendronate): magnesium reduces absorption; space by 30 minutes. Thyroid medication (levothyroxine): same chelation issue; space by 30-60 minutes. CKD patients (stages 3-5) can accumulate magnesium and develop hypermagnesemia at supplemental doses safe for the general population; nephrologist guidance required.
Upper limit. The NIH ODS Upper Limit (UL) for supplemental magnesium (not from food) is 350 mg/day for adults. Higher doses can produce loose stools and, rarely in CKD patients, dangerous hypermagnesemia.
Bottom line
For competitive athletes needing NSF Certified for Sport or users who specifically value pharmaceutical-grade manufacturing, Thorne Magnesium Bisglycinate Powder is the answer at $0.66 per serving. For most non-competitive users who want real chelated magnesium at value pricing from an established manufacturer, NOW Magnesium Glycinate delivers the same active compound at the same effective dose for a fraction of the price.
Frequently Asked Questions
For competitive athletes needing NSF Certified for Sport or users who specifically value pharmaceutical-grade manufacturing standards, yes. For most non-competitive users, NOW delivers the same active compound at the same effective dose for a fraction of the price.
Yes, functionally. Both describe the same chelate structure: one magnesium atom bonded with two glycine molecules. Some brands use bisglycinate to emphasize the 2:1 glycine-to-magnesium ratio; others use glycinate as shorthand. From a reputable manufacturer, both are the same compound with the same absorption profile.
Both work. Most clinical sleep trials with magnesium glycinate use 300-500 mg elemental magnesium taken 30-60 minutes before bed; effects build over 1-2 weeks. Thorne's powder format allows finer dose titration. NOW's tablet format is convenient at fixed doses.
Neither carries formal halal certification. Both use vegetarian tablet or powder formats. The glycine source (synthetic vs animal hydrolysis) is the verification piece for halal-strict consumers; both brands generally use synthetic glycine. Email customer service to confirm.
Space magnesium from tetracyclines (doxycycline) by 2-4 hours and from fluoroquinolones (ciprofloxacin) by 4-6 hours; magnesium chelates these drugs in the GI tract and reduces absorption. Also space from bisphosphonates (alendronate) by 30 minutes.
The NIH ODS Upper Limit (UL) for supplemental magnesium (not from food) is 350 mg/day for adults. Higher doses can produce diarrhea and, rarely in CKD patients, dangerous hypermagnesemia. The RDA of 320-420 mg includes food sources; the 350 mg UL applies to supplements specifically.