Best Magnesium L-Threonate Supplements 2026: Cost per Effective Dose

By Erin Rose · Updated July 22, 2026 · Methodology · About Us

Top pick for Magnesium L-Threonate: Life Extension Neuro-Mag Magnesium L-Threonate (90 Capsules) — 144mg per 3 capsules (2,000 mg Magtein / 144 mg elemental), $1.02/day. Our best-value pick.

All Magnesium L-Threonate Supplements Compared

All 3 products sorted by cost per clinically-effective daily dose (lowest first). Dose, certification, and pricing verified against NIH DSLD and manufacturer data.

Magnesium L-Threonate supplements ranked by cost per effective daily dose. Prices as of July 22, 2026.
Product	Brand	Dose / Serving	Cost / Day	Certification	Pick	Buy
Double Wood Magnesium L-Threonate (120 Capsules)	Double Wood	144mg / 4 capsules (2,000 mg Magtein)	$1.00	None		Buy
Life Extension Neuro-Mag Magnesium L-Threonate (90 Capsules)	Life Extension	144mg / 3 capsules (2,000 mg Magtein / 144 mg elemental)	$1.02	None	Best Value	Buy
NOW Magtein Magnesium L-Threonate (90 Veg Capsules)	NOW Foods	144mg / 3 capsules (2,000 mg Magtein)	$1.03	None		Buy

Our Picks

Best Value: Life Extension Neuro-Mag Magnesium L-Threonate (90 Capsules)

144mg per 3 capsules (2,000 mg Magtein / 144 mg elemental). $1.02/day. 30 servings per container at $30.78.

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How We Rank Magnesium L-Threonate Supplements

Every product is evaluated on three criteria:

Cost per clinically-effective daily dose. Not cost per pill or cost per bottle. We calculate what it actually costs per day to take the dose used in clinical trials.
Third-party certification. USP Verified, NSF Certified for Sport, and ConsumerLab Approved indicate independent testing for purity, potency, and contaminants.
Bioavailable form. We prioritize products using the specific chemical form shown to be most effective in published research.

Rankings are not influenced by affiliate commissions. We earn the same commission regardless of which product you choose. Read our full methodology.

Personalize Your Magnesium L-Threonate Choice

Not sure which magnesium l-threonate supplement is right for you? Use our free tools:

DNA Supplement Analyzer — upload 23andMe or AncestryDNA data to check for genetic variants affecting magnesium l-threonate metabolism. Runs entirely in your browser.
Lab Results Interpreter — enter your blood test values to get personalized dosing recommendations.
Supplement Stack Builder — build a complete protocol based on your age, sex, medications, and goals.
Supplement Audit — already taking magnesium l-threonate? Check if you have the right form and dose.