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✦ AI Overview

Double Wood Supplements Magnesium L-Threonate (Magtein®) by Double Wood Supplements is a high-absorption magnesium supplement featuring Magtein® — the only form of magnesium clinically proven to cross the blood-brain barrier and support magnesium levels in the brain. Formulated for cognitive function, healthy sleep habits, and neurological support. 2,000 mg Magnesium L-Threonate per serving (144 mg elemental magnesium) — 100 capsules, 25 servings per bottle.

🧠 Brain Magnesium Support 💤 Healthy Sleep Habits 📊 Clinically Studied Magtein® ✅ Gluten Free & Non-GMO
🌍 Worldwide Delivery in 5–10 Days✅ Duties & Taxes PrepaidNo extra charges at delivery — what you pay at checkout is all you pay.
🏷️ Volume DiscountBuy 2 or more & save 5%Discount applied automatically at checkout.
✓ Gluten Free ✓ Non-GMO ✓ Made in USA ✓ Third Party Tested ✓ cGMP Facility

Key Features

  • The Only Magnesium That Crosses the Blood-Brain Barrier — Magtein® (magnesium L-threonate) is the only form of magnesium clinically proven to raise magnesium levels in the brain, supporting neurological function from the inside out.
  • Clinically Studied for Cognitive Health — Multiple peer-reviewed clinical studies demonstrate that magnesium L-threonate supports cognitive function, working memory, and overall brain health.
  • Supports Healthy Sleep Habits — Magnesium plays a key role in regulating neurotransmitters and melatonin pathways; Magtein®’s brain-targeted delivery makes it particularly effective for supporting healthy sleep quality.
  • High Bioavailability — The L-threonate chelate enhances magnesium absorption and transport across the blood-brain barrier compared to other magnesium forms such as oxide or citrate.
  • 100 Capsules — 25 Servings (4 capsules/day) — Manufactured in the USA by Double Wood Supplements in a cGMP facility; Gluten Free, Non-GMO, Third Party Tested.

Product Overview

Double Wood Supplements Magnesium L-Threonate features Magtein® — a patented, clinically studied form of magnesium developed by researchers at MIT. Unlike conventional magnesium supplements (oxide, citrate, glycinate), magnesium L-threonate is uniquely able to cross the blood-brain barrier and raise magnesium concentrations in the brain, where magnesium plays a critical role in synaptic plasticity, memory formation, and neurological function.

Multiple clinical studies have demonstrated that Magtein® supplementation supports cognitive function, working memory, and healthy sleep habits. It is widely used by individuals seeking targeted brain health support, age-related cognitive maintenance, or improved sleep quality without sedative effects. Manufactured in the USA in a cGMP-certified facility and third-party tested for purity and potency.

Technical Specifications

Brand / Vendor Double Wood Supplements
SKU B01M4GM9R1
Category Minerals / Brain Health
Active Ingredient Magnesium L-Threonate (as Magtein®)
Magnesium Per Serving 2,000 mg Magnesium L-Threonate (144 mg elemental magnesium)
Serving Size 4 Capsules
Capsule Count 100 Capsules
Servings Per Container 25
Capsule Type Gelatin (not vegan)
Manufactured In USA (cGMP Facility)
Shipping Weight 0.38 lb

Supplement Facts

Serving Size: 4 CapsulesServings Per Container: 25
Amount Per Serving % Daily Value
Magnesium L-Threonate (Magtein®) — 2,000 mg †
Providing elemental magnesium — 144 mg 34%

† Daily Value not established.

Other Ingredients: Gelatin (Capsule), Rice Flour.
Note: Capsules contain Gelatin (not suitable for vegans or vegetarians). Always verify full ingredient listings on physical product label upon receipt.

📊 Dosage & Usage Guide

Always follow label directions. Maximum dose: 8 capsules (4 grams) per day.

Demographic Recommended Dose Frequency & Directions
Adults (18+) 4 Capsules (2,000 mg) Take 4 capsules per day in divided doses: 2 capsules (1 gram) in the morning, and 2 capsules (1 gram) two hours before sleep. In the first week, 2 capsules at night is recommended. Maximum: 8 capsules (4 grams) per day.

💡 How to Use

Suggested Use: Take 4 capsules (2 grams) per day in divided doses — 2 capsules (1 gram) in the morning, and 2 capsules (1 gram) two hours before sleep. In the first week of taking Magtein®, 2 capsules at night is recommended to assess tolerance.

Precautions: Consult your doctor if taking prescription drugs along with Magtein®. Not recommended for children or women who are pregnant or breastfeeding. Do not consume more than 8 capsules per day. Magtein® may induce sleepiness, drowsiness, or headaches — this may indicate a magnesium deficiency and is temporary. Reduce the dosage or consult a doctor if conditions persist for more than one week. Do not operate heavy machinery until you know how it affects you. Keep out of reach of children.

Frequently Asked Questions

What is Magtein®, and why is it different from other magnesium supplements?

Magtein® is a patented form of magnesium L-threonate developed by researchers at MIT. It is the only form of magnesium clinically proven to cross the blood-brain barrier and raise magnesium concentrations in the brain. Most common magnesium forms — such as magnesium oxide, citrate, or glycinate — are primarily absorbed in the gut and support systemic magnesium levels, but have limited ability to increase brain magnesium. Magtein®’s unique L-threonate chelate enables it to be transported across the blood-brain barrier, making it specifically effective for neurological and cognitive applications.

How does Magnesium L-Threonate support cognitive function and memory?

Magnesium plays a critical role in synaptic plasticity — the brain’s ability to strengthen or weaken connections between neurons in response to activity, which is the cellular basis of learning and memory. By raising magnesium levels specifically in the brain, Magtein® supports the density and function of synaptic connections. Multiple peer-reviewed clinical studies have demonstrated that magnesium L-threonate supplementation supports working memory, short-term and long-term memory recall, and overall cognitive performance, particularly in aging adults.

Why is the serving size 4 capsules? Can I take fewer?

The clinical studies on Magtein® used a dose of approximately 2,000 mg (2 grams) of magnesium L-threonate per day — which is 4 capsules of this product. The label recommends splitting this into 2 capsules in the morning and 2 capsules two hours before sleep. In the first week, starting with just 2 capsules at night is recommended to assess tolerance. You may take fewer capsules, but the full 4-capsule dose is what has been studied clinically for cognitive and sleep benefits.

Is this product suitable for vegans or vegetarians?

No — this product uses Gelatin capsules, which are derived from animal sources and are not suitable for vegans or vegetarians. If you require a vegan magnesium L-threonate supplement, look for products that specify vegetable cellulose (HPMC) capsules.

Can Magnesium L-Threonate cause digestive side effects?

Magnesium L-threonate is generally well-tolerated and is less likely to cause the laxative effect associated with high doses of magnesium oxide or citrate. Some individuals may experience mild sleepiness, drowsiness, or headaches when starting — this may indicate a magnesium deficiency and is typically temporary. Start with 2 capsules at night in the first week to assess tolerance, then increase to the full 4-capsule dose.

Can I take Magnesium L-Threonate alongside other magnesium supplements or nootropics?

Yes — magnesium L-threonate is commonly stacked with other magnesium forms and nootropic supplements. Be mindful of total daily magnesium intake from all sources; the tolerable upper intake level for supplemental magnesium is 350 mg/day of elemental magnesium for adults. Each serving of this product provides 144 mg of elemental magnesium. Consult your healthcare provider if you are taking multiple magnesium-containing supplements or prescription medications.

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