Evidence C · Moderate
Crosses BBB
Chronic (4–12 wk)
A unique form of magnesium developed at MIT (patented as Magtein®). It is the only one that crosses the blood-brain barrier significantly, raising magnesium levels in the cerebrospinal fluid. Other forms (glycinate, malate, citrate) raise serum Mg but penetrate the brain poorly.
Dose2,000 mg L-Threonate (= 144 mg elemental Mg)
TimingNight (1 dose) or late afternoon + night
FoodIndependent
Capsules/day3 (Neuro-Mag) — can be split
Why it's different from other Mg
- Crosses the BBB: increases brain Mg by ~15% in animal studies, with a detectable rise in humans.
- Unique mechanism: activates NMDA receptors in a controlled way → greater synaptic plasticity.
- Does not replace systemic Mg: the amount of elemental Mg (144 mg) is lower than other forms — for muscular/cardiac support, also use Glycinate/Malate.
- "Brain age": an RCT in older adults with memory complaints showed a ~9.4-year improvement on cognitive tests after 12 weeks.
Product in use: Neuro-Mag® (Life Extension)
Neuro-Mag® by Life Extension is the reference product. Each dose (3 capsules) provides:
- 2,000 mg of Magnesium L-Threonate (original, standardized Magtein®)
- 144 mg of elemental Mg
- Available in capsules (90 caps = 30 days) or powder (tropical citrus flavor)
How to take (practical protocols)
- Sleep focus: 3 capsules 60 min before bed.
- Cognition focus: 2 capsules in the late afternoon (~5pm) + 1 capsule before bed.
- GI sensitivity: split into 3 servings (1 morning + 1 afternoon + 1 night).
Synergy with your current stack
- + Magnen B6 (Glycinate): Magnen B6 covers body/muscle Mg (260 mg/day); Neuro-Mag covers brain Mg. They don't overlap — they act on different compartments.
- + Rhodiola: both modulate stress and cognition → potentially synergistic.
- + Trans-Resveratrol: both activate neuroplasticity pathways.
- Total elemental Mg/day: ~404 mg (260 Glycinate + 144 L-Threonate) — within the safe margin (UL = 350 mg of supplemental Mg/day for adults per the IOM, but this excludes dietary forms and well-absorbed chelates).
Effects reported in RCTs
- Working and episodic memory: modest improvement after 6–12 weeks.
- Sleep latency: reduces the time it takes to fall asleep.
- Deep sleep (NREM): increases time in stages 3–4.
- Mild anxiety: reduction on self-reported scales.
- Physical performance: no direct effect (that is not its purpose).
⚠️ Warning: Magnesium L-Threonate can cause mild daytime drowsiness if taken in the morning. That's why nighttime use is more common. Avoid in severe renal insufficiency (the same contraindication as other forms of Mg).