Advanced Formula 2,000 mg Magnesium L-Threonate Supports Cognitive Health Dietary Supplement Quality Matters: Non Gmo Project Verified Nsf Certified Gluten Free Third Party Tested cGMP Compliant Certified Nutrition - American Vegetarian Association Magnesium L-Threonate has been shown to cross the blood-brain barrier unlike other magnesium forms like glycinate, citrate, or oxide.