NOW Foods Magnesium Glycinate Review

Mostly brand familiarity. NOW Foods has 30+ years in the supplement category and runs a credible in-house lab program — but the underlying bisglycinate molecule is the same generic chelate as Doctor's Best (which adds the TRAACS patent) and Nutricost (which is $4 cheaper). The household-brand recognition is worth something to risk-averse buyers who'd rather buy a name they've seen at every Sprouts and Vitamin Shoppe in the country. Functionally, you're paying $2-4/month for that familiarity premium.

Marginally. Tablets dissolve slightly slower than capsules because of the binding agents — peak plasma Mg lands 10-15 minutes later. For sleep dosing, take it 75-90 min pre-bed (vs 60 min for capsules). The trade-off: tablets are usually cheaper to manufacture and store, which helps NOW hit the $16/mo price point. If you're optimizing for fastest onset, prefer Doctor's Best tablets (similar) or Thorne powder (faster). If a 15-minute onset delta doesn't matter, tablets are fine.

Yes — NOW operates one of the most-respected in-house QC labs in the supplement industry. They publish methodology, run cross-validation against third-party labs, and have a track record of voluntary recalls when issues surface (rare in this category). The NSF-registered facility designation is real. The gap vs Doctor's Best is that Doctor's Best uses the patented TRAACS chelate (Albion Labs supplier with its own independent verification) on top of brand-level QC — slightly stronger audit stack.

It's the floor of the trial-measurable window. Held 2002 used 240 mg, Abbasi 2012 used 500 mg. NOW's 200 mg per 2-tab serving is the start-here dose. Most users land at 2-3 servings/day (400-600 mg) after a 1-2 week ramp for full sleep + cramp benefit. At 200 mg/day the 180-tablet bottle covers 90 days — solid runway. At 400 mg/day it's 45 days, shorter than Doctor's Best's 4-month bottle at the same intake.

Three cases: (1) You shop at brick-and-mortar health stores and want the bottle you've physically seen on the shelf. (2) You value 30-year brand stability + voluntary-recall track record over patent-tier verification. (3) You're a returning NOW customer with brand loyalty across multiple products and want supplement-stack consistency. For first-time magnesium buyers without specific brand affinity, Doctor's Best is the better default at the same trusted-brand tier.

Kosher certification (Orthodox Union, in NOW's case) means independent audit of ingredients + manufacturing processes against kosher law. For Jewish buyers it's a hard requirement; for non-Jewish buyers it's a tertiary quality signal (kosher certification correlates with cleaner supply chain). Non-GMO is the industry default for magnesium — most major brands carry it. Neither feature is unique to NOW, but they're verifiable and on-label.

Standard tablet size — slightly larger than Doctor's Best's tablets because NOW uses a different binding compression. No reported swallowing issues from typical users; sensitive populations (elderly, post-bariatric) may prefer capsule alternatives like Pure Encapsulations or powder format like Thorne. The tablets are uncoated, so they dissolve at standard rate without delayed-release behavior.

1. [1] Abbasi 2012 PMID 23853635 — The effect of magnesium supplementation on primary insomnia in elderly. 500 mg/day elemental magnesium for 8 weeks improved sleep efficiency and onset latency. Cornerstone insomnia RCT for dose anchoring.
2. [2] Held 2002 PMID 12163983 — Oral Mg(2+) supplementation reverses age-related neuroendocrine and sleep EEG changes in humans. 240 mg elemental Mg for 20 days increased slow-wave sleep and reduced cortisol. NOW's 200 mg/serving lands at the floor of this trial-measurable window.
3. [3] Schuette 1994 PMID 7815675 — Bioavailability of magnesium diglycinate vs magnesium oxide. Bisglycinate significantly higher intestinal absorption than oxide. Foundational evidence behind the chelate form choice.
4. [4] Walker 2003 PMID 14596323 — Mg citrate found more bioavailable than other Mg preparations. Comparative absorption: citrate > glycinate > oxide. Frames the chelate hierarchy and contextualizes the bisglycinate choice.
5. [5] Rosanoff 2012 PMID 22364157 — Suboptimal magnesium status in the United States. ~50% of US adults below the EAR for magnesium. Population-level case for routine supplementation.
6. [6] Uwitonze 2018 PMID 29480918 — Role of magnesium in vitamin D activation and function. Magnesium is the obligate cofactor for vitamin D activation. Supports the D3 + K2 co-stack recommendation for magnesium responders.