Momentous Magnesium L-Threonate is built specifically for the brain. Each serving delivers 2g of Magtein® — the only patented form of magnesium L-threonate clinically shown to effectively cross the blood-brain barrier and elevate brain magnesium levels.
Most magnesium forms (citrate, oxide, glycinate) work systemically in the body but don't deliver significant amounts to the brain. Magnesium L-threonate combines magnesium with L-threonic acid — a metabolite of vitamin C — to act as a carrier that escorts magnesium across the blood-brain barrier.
Key benefits:
• Sleep quality — supports deeper, more restorative sleep without sedation or grogginess
• Cognitive function — supports focus, memory retention, and mental clarity
• Synaptic health — increases synaptic density and plasticity, critical for learning and memory
• Nervous system support — magnesium is a cofactor in 600+ enzymatic reactions including those that calm the nervous system
• Stress response — supports the body's natural relaxation mechanisms
Magtein® was developed by a team of scientists at MIT, including the renowned neuroscientist Dr. Guosong Liu. It's the most studied form of magnesium L-threonate with multiple animal and human studies supporting its neurological benefits.
Take 3 capsules 30–60 minutes before bed for sleep support, or earlier in the day for cognitive support — some users find it sedating in the morning, so test your response. Sleep improvements often noticeable within 7 days; full cognitive benefits build over 3–4 weeks of consistent use.
Momentous Magnesium L-Threonate is NSF Certified for Sport®, vegan, gluten-free, and GMO-free. Independently tested for banned substances every batch.
These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult with your doctor to see if this product is right for you.
Most magnesium forms (citrate, glycinate, oxide) work in the body but don't effectively reach the brain. Magnesium L-threonate — specifically Magtein® — uses L-threonic acid as a carrier to cross the blood-brain barrier. It's the only form clinically shown to raise brain magnesium levels.
When should I take it?
For sleep support, take 3 capsules 30–60 minutes before bed. For cognitive support, take it in the morning or early afternoon. Some users find it slightly sedating, so test your individual response with daytime dosing first.
How long until I notice results?
Sleep quality improvements are often noticeable within 7 days. Full cognitive benefits — focus, memory, mental clarity — build over 3–4 weeks as brain magnesium levels rise. Be consistent.
What's the difference between Magtein® and generic magnesium L-threonate?
Magtein® is the patented, clinically studied form developed at MIT. Multiple human and animal studies back its specific role in raising brain magnesium and supporting synaptic plasticity. Generic magnesium L-threonate may use lower-quality raw material without the same research.
Can I take this with other Momentous sleep products?
Yes — Magnesium L-Threonate stacks well with Apigenin and L-Theanine for sleep (this is the Nightly Sleep combination). You can also take it alone if you only need magnesium support.
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Earn 40 points for every $1 spent equaling 5% cash back
DESCRIPTION
Momentous Magnesium L-Threonate is built specifically for the brain. Each serving delivers 2g of Magtein® — the only patented form of magnesium L-threonate clinically shown to effectively cross the blood-brain barrier and elevate brain magnesium levels.
Most magnesium forms (citrate, oxide, glycinate) work systemically in the body but don't deliver significant amounts to the brain. Magnesium L-threonate combines magnesium with L-threonic acid — a metabolite of vitamin C — to act as a carrier that escorts magnesium across the blood-brain barrier.
Key benefits:
• Sleep quality — supports deeper, more restorative sleep without sedation or grogginess
• Cognitive function — supports focus, memory retention, and mental clarity
• Synaptic health — increases synaptic density and plasticity, critical for learning and memory
• Nervous system support — magnesium is a cofactor in 600+ enzymatic reactions including those that calm the nervous system
• Stress response — supports the body's natural relaxation mechanisms
Magtein® was developed by a team of scientists at MIT, including the renowned neuroscientist Dr. Guosong Liu. It's the most studied form of magnesium L-threonate with multiple animal and human studies supporting its neurological benefits.
Take 3 capsules 30–60 minutes before bed for sleep support, or earlier in the day for cognitive support — some users find it sedating in the morning, so test your response. Sleep improvements often noticeable within 7 days; full cognitive benefits build over 3–4 weeks of consistent use.
Momentous Magnesium L-Threonate is NSF Certified for Sport®, vegan, gluten-free, and GMO-free. Independently tested for banned substances every batch.
These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult with your doctor to see if this product is right for you.
Most magnesium forms (citrate, glycinate, oxide) work in the body but don't effectively reach the brain. Magnesium L-threonate — specifically Magtein® — uses L-threonic acid as a carrier to cross the blood-brain barrier. It's the only form clinically shown to raise brain magnesium levels.
When should I take it?
For sleep support, take 3 capsules 30–60 minutes before bed. For cognitive support, take it in the morning or early afternoon. Some users find it slightly sedating, so test your individual response with daytime dosing first.
How long until I notice results?
Sleep quality improvements are often noticeable within 7 days. Full cognitive benefits — focus, memory, mental clarity — build over 3–4 weeks as brain magnesium levels rise. Be consistent.
What's the difference between Magtein® and generic magnesium L-threonate?
Magtein® is the patented, clinically studied form developed at MIT. Multiple human and animal studies back its specific role in raising brain magnesium and supporting synaptic plasticity. Generic magnesium L-threonate may use lower-quality raw material without the same research.
Can I take this with other Momentous sleep products?
Yes — Magnesium L-Threonate stacks well with Apigenin and L-Theanine for sleep (this is the Nightly Sleep combination). You can also take it alone if you only need magnesium support.
No FAQs match your search.
EARN REWARDS
All purchases accumulate points which can be used to redeem for discounts on any product. Enroll or view your current rewards balance here.
Earn 40 points for every $1 spent equaling 5% cash back
Recommended Thickness
6mm:
General-purpose for home fitness
8mm:
Home + light commercial use. Suitable for functional trainers, squat racks, treadmills
9mm:
Popular in commercial gyms, ideal for CrossFit & heavier dropsMost Popular
12mm:
Heavy-duty, great for Olympic lifting zones
18mm:
Industrial strength, used for powerlifting & stables
Sleep
Focus
Stress Support
Recovery
NSF for Sport
Non-GMO
Vegan
Gluten-Free
Living.Fit Rewards
All purchases accumulate points which can be used to redeem for discounts on any product.
Earn 40 points for every $1 spent which can be redeemed for discounts on any product
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