Life Extension Neuro-Mag, Double Wood Magtein, and Nutricost Magtein all list the identical patented ingredient on their Supplement Facts panels: Magnesium L-Threonate, sold under the Magtein trademark (AIDP Inc., U.S. Patent), yet diverge on magnesium per capsule, capsule count per bottle, cost per gram of Magtein, excipient panels, and brand-level testing disclosures. Same molecule. Same patent. Three different bottles with three different spec priorities. We pulled the Supplement Facts panels on all three to compare exactly what you are buying per capsule and what you are paying per gram of Magnesium L-Threonate.
Magtein Supplement Facts Comparison: Life Extension vs. Double Wood vs. Nutricost
All three products list Magnesium L-Threonate as the active ingredient, sourced under the Magtein trademark from AIDP Inc., the U.S. patent holder for this specific magnesium compound. The Magtein molecule itself carries roughly 7-8% elemental magnesium by weight. A 2,000mg dose of Magtein yields approximately 144-160mg of elemental magnesium. The ingredient is identical across all three bottles. The differences are in capsule count, excipient panel, brand-level testing, and cost per gram of Magtein.
| Spec | Life Extension Neuro-Mag | Double Wood Magtein | Nutricost Magtein |
|---|---|---|---|
| Active Ingredient | Magnesium L-Threonate (Magtein) | Magnesium L-Threonate (Magtein) | Magnesium L-Threonate (Magtein) |
| Magtein per Serving | 2,000 mg (3 capsules) | 2,000 mg (4 capsules) | 2,000 mg (4 capsules) |
| Approx. Elemental Mg per Serving | ~144-160 mg | ~144-160 mg | ~144-160 mg |
| Capsules per Serving | 3 capsules | 4 capsules | 4 capsules |
| Mg per Capsule (Magtein) | ~667 mg | ~500 mg | ~500 mg |
| Capsules per Bottle | 90 capsules (30 servings) | Varies by SKU (typically 90-180 ct) | Varies by SKU (typically 90-180 ct) |
| Excipients Listed | Vegetable cellulose (capsule), microcrystalline cellulose, silica, vegetable stearate | Hypromellose (capsule), microcrystalline cellulose, magnesium stearate | Hypromellose (capsule), magnesium stearate, silicon dioxide |
| Brand Testing Disclosure | Life Extension quality standards; third-party tested | Third-party tested (per brand disclosure) | Third-party tested (per brand disclosure) |
| Magtein Trademark Displayed | Yes (prominently on label) | Yes (prominently on label) | Yes (prominently on label) |
| Relative Cost per Gram of Magtein | Moderate to high | Moderate | Lowest |
The Magtein molecule is identical across all three products. The active ingredient panel lists the same compound at the same 2,000mg per serving across all three brands. The differences are in capsule size per unit (Life Extension packs 667mg per capsule vs. 500mg for the other two), excipient panel composition, bottle count math, and cost per gram of Magtein. Same active. Different capsule efficiency. Different price tag.
Buying Magtein from three different brands is like buying the same engine from three different car dealerships. The engine block is identical. The patent number on the side of the block is the same. One dealer gives you three keys. The other two give you four. The sticker price is different at each lot. You are buying the same motor. You are comparing the dealership, the key count, and the final invoice.
Label Deep Dive: What Each Product’s Supplement Facts Panel Tells You
Life Extension Neuro-Mag lists Magnesium L-Threonate (as Magtein) at 2,000mg per three-capsule serving, with an excipient panel that includes vegetable cellulose, microcrystalline cellulose, silica, and vegetable stearate. The product is manufactured under Life Extension’s quality standards with third-party testing disclosed. The 667mg of Magtein per capsule means fewer capsules per serving (3) compared to Double Wood and Nutricost (4). The bottle contains 90 capsules for 30 servings. Life Extension is the legacy brand in the cognitive supplement category. The label carries that brand weight alongside the Magtein trademark.
- Magtein per Capsule: ~667 mg (highest per-capsule density of the three)
- Capsules per Serving: 3 (fewest of the three)
- Excipients: Vegetable cellulose capsule, microcrystalline cellulose, silica, vegetable stearate
- Brand Profile: Life Extension — long-established supplement manufacturer with published quality standards
Double Wood Magtein lists Magnesium L-Threonate (as Magtein) at 2,000mg per four-capsule serving, with an excipient panel that includes hypromellose, microcrystalline cellulose, and magnesium stearate. Double Wood is a brand with a strong following in the nootropic supplement space. The label is clean, the Magtein trademark is prominent, and the per-capsule Magtein load is 500mg. The bottle count varies by SKU. Double Wood positions as the straightforward, no-unnecessary-additives option. The label reflects that positioning.
- Magtein per Capsule: ~500 mg
- Capsules per Serving: 4
- Excipients: Hypromellose capsule, microcrystalline cellulose, magnesium stearate
- Brand Profile: Double Wood — known in nootropic supplement circles for transparent labeling
Nutricost Magtein lists Magnesium L-Threonate (as Magtein) at 2,000mg per four-capsule serving, with an excipient panel that includes hypromellose, magnesium stearate, and silicon dioxide. Nutricost is a value-oriented supplement brand. The per-capsule Magtein load is 500mg, matching Double Wood. The bottle count varies by SKU. Nutricost leads on cost per gram of Magtein. The excipient panel is lean. The brand does not carry the same longevity or nootropic-specific reputation as Life Extension or Double Wood.
- Magtein per Capsule: ~500 mg
- Capsules per Serving: 4
- Excipients: Hypromellose capsule, magnesium stearate, silicon dioxide
- Brand Profile: Nutricost — value-tier supplement manufacturer with third-party testing disclosure
Who Each Magtein Product Fits, Based on the Spec Sheet
The Magtein molecule is identical across all three products. The capsule count per serving, cost per gram, excipient panel, and brand testing disclosures are the spec sheet differentiators. Match the label to your buying criteria.
- The Capsule-Efficiency Buyer: Life Extension Neuro-Mag packs 667mg of Magtein per capsule, the highest per-capsule density. Three capsules deliver the 2,000mg serving. Four capsules for Double Wood and Nutricost to reach the same Magtein total. If swallowing fewer capsules per serving matters to your buying decision, the Neuro-Mag label leads on capsule efficiency.
- The Budget Buyer: Nutricost Magtein leads on cost per gram of Magtein. The excipient panel is lean. The brand is value-positioned. You are paying for the Magtein molecule, not for brand equity. The trade-off is four capsules per serving versus three for Life Extension.
- The Nootropic-Stack Buyer: Double Wood Magtein sits in the middle on cost per gram with a clean excipient panel and a brand reputation rooted in the nootropic supplement space. If you already purchase other nootropic supplements and trust the Double Wood label architecture, the Magtein SKU matches the brand format you are familiar with. See Double Wood Lion’s Mane for a comparison of another Double Wood cognitive supplement label.
- The Brand-Longevity Buyer: Life Extension Neuro-Mag carries the Life Extension brand name, a manufacturer with decades of supplement formulation history and published quality standards. If the brand name on the bottle is a buying criterion, Life Extension has the longest track record of the three.
- The Excipient-Aware Buyer: All three products use different capsule materials and excipient panels. Life Extension uses vegetable cellulose capsules with silica and vegetable stearate. Double Wood and Nutricost use hypromellose capsules with microcrystalline cellulose and magnesium stearate (Double Wood) or silicon dioxide (Nutricost). Read the other ingredients list on each label. The capsule material and excipient choices differ across all three.
- Who Should Skip Magtein Entirely: Magnesium L-Threonate delivers roughly 144-160mg of elemental magnesium per 2,000mg serving. If you need high elemental magnesium intake, a different magnesium form like magnesium glycinate or magnesium citrate delivers more elemental magnesium per gram. Magtein is a specific patented compound. It is not a general-purpose magnesium supplement. For a different magnesium category entirely, see Thorne’s supplement line for magnesium formats beyond Magtein.
Magtein Pros and Cons: The Spec Sheet, Unspun
The Advantage (All Three Products)
- Identical Patented Molecule: All three list Magnesium L-Threonate under the Magtein trademark from AIDP Inc. Same active ingredient. Same patent. Same manufacturer of the raw compound. The Magtein trademark on the label is verifiable. If a product claims Magtein, the trademark should appear on the Supplement Facts panel.
- Fully Disclosed Magnesium Amounts: All three labels list the Magtein amount in milligrams per serving. No proprietary blends. No hidden magnesium totals behind a matrix.
- Third-Party Testing Disclosures: All three brands disclose some form of third-party testing on their product labeling or website.
The Trade-offs (All Three Products)
- Low Elemental Magnesium Yield: Magtein is roughly 7-8% elemental magnesium by weight. A 2,000mg serving delivers approximately 144-160mg of elemental magnesium. Magnesium glycinate and magnesium citrate deliver significantly more elemental magnesium per gram. Magtein is a specific patented compound purchased for the L-threonate carrier. It is not purchased for elemental magnesium efficiency.
- Multiple Capsules per Serving: Three to four capsules are required to reach the 2,000mg serving. Not a one-capsule product.
- Higher Cost per Gram of Magnesium: Magtein costs more per gram of elemental magnesium than magnesium glycinate, citrate, or oxide. The patent premium and the L-threonate carrier are the line items that justify the price difference on the spec sheet.
- Not a General Magnesium Supplement: Magtein is a single-form magnesium supplement. It does not contain magnesium glycinate, magnesium citrate, or other magnesium forms for broader magnesium coverage. It does not contain vitamin D3, vitamin K2, or zinc. Pairing with a D3/K2 supplement is a separate purchase decision.
Magtein FAQ: Label Math, Trademarks, and Ingredient Verification
- What is the difference between Magtein and generic Magnesium L-Threonate on a label?
- Magtein is the registered trademark for a specific, patented form of Magnesium L-Threonate manufactured by AIDP Inc. under U.S. patent protection. A label that displays the Magtein logo indicates the product uses AIDP-manufactured Magnesium L-Threonate specifically. A label that lists “Magnesium L-Threonate” without the Magtein trademark may use a non-patented form from a different manufacturer. All three products compared here carry the Magtein trademark on their labels.
- How much elemental magnesium is in a 2,000mg serving of Magtein?
- Magtein (Magnesium L-Threonate) is approximately 7-8% elemental magnesium by weight. A 2,000mg serving of Magtein yields roughly 144-160mg of elemental magnesium. Compare that to magnesium glycinate, which is roughly 14-18% elemental magnesium by weight. The elemental magnesium number is on the Supplement Facts panel. The Magtein weight is the total compound weight including the L-threonate carrier.
- Why does Life Extension Neuro-Mag use 3 capsules per serving while the others use 4?
- Life Extension lists approximately 667mg of Magtein per capsule. Double Wood and Nutricost list approximately 500mg per capsule. The per-capsule Magtein density is higher in the Life Extension capsule, requiring three capsules to reach 2,000mg versus four for the other two brands. The total Magtein per serving is identical at 2,000mg. The capsule count difference is a per-unit density spec, not a total dose difference.
- Are there any differences in the excipient panels I should know about?
- Yes. Life Extension uses a vegetable cellulose capsule with microcrystalline cellulose, silica, and vegetable stearate. Double Wood uses a hypromellose capsule with microcrystalline cellulose and magnesium stearate. Nutricost uses a hypromellose capsule with magnesium stearate and silicon dioxide. The capsule material and flow agent choices are different across all three brands. The active ingredient is identical.
- How do I verify the Magtein trademark is legitimate on a product label?
- The Magtein trademark and logo are owned by AIDP Inc. A product label displaying the Magtein name or logo should be sourcing from AIDP’s patented Magnesium L-Threonate supply. If the Magtein trademark appears on the label, the raw ingredient is the same AIDP-manufactured compound across all three brands. The brand then formulates it into capsules with their own excipient choices.
Magtein Final Verdict: Same Molecule, Three Different Bottle Priorities
All three products contain the identical patented ingredient: Magnesium L-Threonate sold under the Magtein trademark from AIDP Inc. The Life Extension Neuro-Mag leads on capsule efficiency (3 capsules per serving vs. 4) and brand longevity. The Double Wood Magtein leads on clean-label positioning within the nootropic supplement space. The Nutricost Magtein leads on cost per gram of Magtein. None of the three is defective. The molecule inside is identical. Pick the bottle that matches your capsule-count preference and your budget.
Verdict: Same Patented Molecule, Three Spec Priorities
Capsule efficiency (Life Extension). Nootropic brand positioning (Double Wood). Cost per gram of Magtein (Nutricost). The active ingredient is identical. Choose your bottle.
*Prices, capsule counts, and formulations subject to change. Verify the Supplement Facts panel on the live listing before purchase. Statements have not been evaluated by the FDA. These products are not intended to diagnose, treat, cure, or prevent any disease.
The Magtein Lexicon: Terms on the Supplement Facts Panel
- Magnesium L-Threonate
- A patented magnesium compound consisting of magnesium bound to L-threonic acid, a vitamin C metabolite. Sold under the registered trademark Magtein by AIDP Inc. Roughly 7-8% elemental magnesium by weight. The remaining weight is the L-threonate carrier molecule.
- Magtein
- The registered trademark of AIDP Inc. for their patented Magnesium L-Threonate ingredient. A label displaying the Magtein logo indicates the raw ingredient was sourced from AIDP, the U.S. patent holder. Products without the Magtein trademark may use non-patented Magnesium L-Threonate from other manufacturers.
- Elemental Magnesium
- The actual magnesium content of a magnesium supplement, expressed in milligrams on the Supplement Facts panel. Different from the total compound weight. Magnesium L-Threonate at 2,000mg yields roughly 144-160mg of elemental magnesium. Magnesium glycinate at 2,000mg yields roughly 280-360mg of elemental magnesium.
- Excipient Panel
- The other ingredients section of the Supplement Facts panel listing capsule materials, fillers, flow agents, and binders. Not the active ingredient. These are the manufacturing compounds that form the capsule and hold the powder together. Hypromellose, microcrystalline cellulose, magnesium stearate, silica, and silicon dioxide are common excipients in Magtein products.
- Hypromellose (Hydroxypropyl Methylcellulose)
- A cellulose-derived polymer used as a vegetarian capsule material. Listed in the other ingredients section of many supplement labels. An alternative to gelatin capsules. Plant-derived. Used by Double Wood and Nutricost Magtein products.
- Vegetable Cellulose
- A plant-derived capsule material listed in the other ingredients section. Used by Life Extension as an alternative to gelatin and hypromellose capsules. Functionally equivalent to hypromellose as a capsule delivery format. Different material on the ingredient panel.
Keep Reading: Magnesium & Supplement Spec Comparisons
- Life Extension Neuro-Mag Full Review — the complete Supplement Facts panel breakdown for the Life Extension Magtein product.
- Double Wood Magtein Full Review — full label analysis of the Double Wood Magtein SKU.
- Nutricost Magtein Full Review — complete ingredient panel and cost-per-gram breakdown for Nutricost Magtein.
- What Is Magnesium L-Threonate? — the structural breakdown of the Magtein molecule, the AIDP patent, and how it differs from other magnesium forms on a spec sheet.
- Double Wood Lion’s Mane Review — another Double Wood cognitive supplement label for comparing the brand’s excipient architecture across products.
- Sports Research D3 + K2 Review — a common stacking partner with magnesium supplementation for comprehensive support.
