3 forms with solid human evidence · each optimizes a different use case. Avoid oxide (4% bioavailability) and citrate if you have irritable bowel.
Mg bound to 2× glycine amino acid
Best for
Ideal use: sleep, anxiety, athletic recovery, general repletion.
Advantages
80% bioavailability · zero laxative effect at 500 mg · glycine provides sleep quality and glutathione precursor.
Disadvantages
Doesn't cross BBB efficiently → not the top form for pure cognition. More expensive (~25 €/month premium).
Magtein® MIT patent
Best for
Ideal use: cognition, memory, executive function post-50.
Advantages
Only form that significantly raises brain Mg (Slutsky 2010). Human RCT evidence in episodic memory.
Disadvantages
Expensive (~35–55 €/month). Only provides ~144 mg Mg per typical dose (1.5 g threonate) → needs glycinate combo for base repletion.
Mg bound to malic acid
Best for
Ideal use: morning fatigue, fibromyalgia, endurance athletes.
Advantages
Bioavailability ~70% · malate is Krebs cycle intermediate → ATP production. Good evidence in fibromyalgia and chronic fatigue.
Disadvantages
Take in morning (slightly stimulant effect). Less evidence than glycinate for sleep.
Ideal use: sleep, anxiety, athletic recovery, general repletion.
Ideal use: cognition, memory, executive function post-50.
Ideal use: morning fatigue, fibromyalgia, endurance athletes.
3 forms with solid human evidence · each optimizes a different use case. Avoid oxide (4% bioavailability) and citrate if you have irritable bowel.