Momentous Magnesium L-Threonate Supplement

Momentous Magnesium L-Threonate Supplement

4.84 reviews
$ 49.95

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Product Details

Momentous Magtein® is a patented form of magnesium L-yhreonate designed for superior absorption into the brain. L-threonate serves as a carrier, helping magnesium cross the blood-brain barrier for improved absorption.

Boosting magnesium levels helps improve cognitive function and supports more than 600 enzymatic reactions, including those that trigger a calming effect on the nervous system and others that play a role in the body’s stress response and relaxation mechanisms.

Taken consistently, Magtein® may enhance sleep quality when used before bed, and improve focus and mental clarity when used during the day.

Product Specs

  • Count: 90 capsules
  • Serving size: 3 capsules
  • Magnesium content: 2,000 mg magnesium L-threonate (~145 mg elemental magnesium)
  • Other ingredients: rice flour, hypromellose (capsule), magnesium stearate, and silica

Key Benefits

  • Calms brain and nervous system activity, leading to less stress and increased feelings of relaxation
  • Crosses the blood-brain barrier more effectively than other versions of magnesium to deliver a more concentrated dose of magnesium where it can help enhance memory, learning, and focus
  • Improves mental clarity during the day and reduces tension at night for more restful sleep.
Safety & Storage

Talk to your doctor before use if you are pregnant, nursing, have a medical condition, or are taking other medications or supplements. Do not exceed the recommended dose unless directed by a qualified medical professional. Discontinue use and seek medical attention if you experience allergic reactions or severe side effects.

Store in a cool, dry place away from direct sunlight, heat, and moisture. Keep the bottle tightly closed when not in use to preserve freshness and potency. Keep out of reach of children to prevent accidental ingestion. Do not use if the safety seal under the cap is broken or missing.

Shipping & Returns

This product is not eligible for returns. Customers have a 60-minute window after placing an order to make changes or cancellations. After this time, in-stock items begin fulfillment and may no longer be altered. Customers experiencing issues with their purchase should contact Momentous for assistance.

Free Shipping for orders $50 and above in contiguous U.S. For orders under $50.00, the shipping rate is $7.99. Orders shipping to Alaska, Hawaii, Puerto Rico, Guam, and Virgin Islands are subject to an additional shipping fee.

Expedited Shipping

  • 2 Business day shipping - $25
  • Overnight shipping - $85

Order must be placed and with approved prescription (if applicable) before 10 am EST to ship same-day. Excludes Sat/Sun delivery.

Expedited shipping is not available:

To Alaska, Hawaii, PO boxes and some rural areas.

During excluded holidays

Please note that your order may ship in multiple packages.

Once your order ships, you will receive a tracking number and estimated date of delivery. Most customers receive their orders within 4-7 days of shipping. Carrier delays are outside of our control.

Find our full Shipping & Returns policy here.

Who It’s Best For

  • People looking to support memory, focus, and cognitive performance
  • Those who struggle to meet recommended daily magnesium needs through foods
  • People who are sensitive to magnesium supplements and capsule ingredients and want a clean, easy-to-digest compound

How It Works

When taken orally, magnesium L-threonate is absorbed by the digestive system and delivers magnesium to the bloodstream as a bioavailable, fast-working compound. The L-threonate acts as a carrier, helping magnesium cross the blood-brain barrier for more targeted and improved absorption. This way, magnesium can get to work supporting the processes involved in memory, learning, relaxation, and sleep regulation.

How to Use It

  • For sleep and relaxation, take three capsules 30 to 60 minutes before bed.
  • For better cognitive function, spread the dose throughout the day, taking one capsule with each meal.
  • Magnesium L-threonate does not have to be taken with food unless you have a sensitive stomach.

Frequently asked questions

When should I take Magnesium L-Threonate?

Magnesium L-Threonate can be taken at different times depending on your wellness goals. For sleep and relaxation, take all three capsules 30 to 60 minutes before bed. If you're using it for cognitive support, consider spreading the dose throughout the day — ideally one capsule with each meal — to promote mental clarity and focus without drowsiness.

Where is Magnesium L-Threonate sourced from?

Momentous sources its Magnesium L-Threonate from the United States. Domestic sourcing helps ensure consistent quality, purity, and adherence to rigorous manufacturing standards from raw material to final product.

Where does the cellulose in Magnesium L-Threonate come from?

The vegetable-derived cellulose used in Momentous Magnesium L-Threonate comes from plant sources and is used to form the capsule that delivers the active ingredients. While the cellulose is plant-based, it may not be corn-free. If you have a corn allergy or sensitivity, consult with your healthcare provider before use.

Why is rice flour added to Magnesium L-Threonate?

Rice flour is used as a natural alternative to magnesium stearate, helping improve capsule consistency and ingredient blending while keeping additive levels low. It’s hypoallergenic, supports clean-label preferences, and ensures quality without synthetic fillers.

Can I take Magnesium Malate and Magnesium L-Threonate together?

Yes, both supplements can be taken together to support different health goals — Magnesium Malate for energy and muscle function and Magnesium L-Threonate for cognitive function and sleep quality. Together, they provide 365 milligrams of magnesium, which falls within general safe intake levels. For personalized guidance, talk to your doctor.

How long does it take for Magnesium L-Threonate to improve sleep quality?

Sleep benefits may become noticeable after a few weeks of consistent use, though individual results vary. Some people feel more rested within days, while others may need several weeks for the supplement to take full effect.

Does Magnesium L-Threonate have any side effects?

Magnesium L-Threonate is generally well-tolerated. In some cases, higher doses can cause mild digestive issues like bloating, cramping, or diarrhea. Sticking to the recommended dosage and taking it with food can help minimize discomfort.

Who should not take Magnesium L-Threonate?

Do not take if you:

  • Have kidney disease or impaired kidney function
  • Are taking multiple supplements, such as high-dose multivitamins with extra magnesium
  • Have rice allergies

Reviews

4.8
Rated 4.8 out of 5 stars
Based on 4 reviews
Total 5 star reviews: 3 Total 4 star reviews: 1 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
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4 reviews
  • Richard s.
    Verified Buyer
    Reviewing
    Momentous Magnesium L-Threonate Supplement
    Rated 5 out of 5 stars
    5/27/26
    effective

    Easy to use and quite effective.

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  • Audrey Z.
    Verified Buyer
    Reviewing
    Momentous Magnesium L-Threonate Supplement
    Rated 4 out of 5 stars
    4/7/26
    Prompt delivery

    Received these quickly. Look forward to trying them. A friend of my said good things about it.

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  • Timothy H.
    Verified Buyer
    Reviewing
    Momentous Magnesium L-Threonate Supplement
    Rated 5 out of 5 stars
    9/7/25
    Magnesium

    This magnesium supplement was a noticeable improvement compared to my previous supplement.

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  • Christine D.
    Verified Buyer
    Reviewing
    Momentous Magnesium L-Threonate Supplement
    Rated 5 out of 5 stars
    7/16/25
    My new go to sleep supplement

    Quality sleep has become a challenge as I age. This preparation of magnesium helps me get more deep sleep and lowers feelings of anxiety. Worth the price.

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