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Source Naturals


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667 mg 90 Caps
Gluten Free
  • Magnesium L-Threonate

  • Supports learning and memory

  • Gluten-free; contains no preservatives or artificial colors

Magtein from Source Naturals is now available in a larger 90-capsule bottle! Magnesium plays an essential role in supporting brain function and health, and Magtein (magnesium L-threonate) delivers it effectively and efficiently. Preliminary research suggests that Magtein may provide more magnesium to the brain than other forms of magnesium. In preclinical studies, Magtein was shown to support healthy memory and learning, as well as healthy brain synapse density in regions of the brain associated with memory.

Contains no yeast, dairy, egg, gluten, soy or wheat. Contains no sugar, starch, salt, preservatives or artificial color, flavor or fragrance.

Product Label

Supplement Facts

Serving Size 3 Capsules

Servings Per Container 30

  Amount Per Serving %Daily Value
Calories 10  
Magnesium (as magnesium L-threonate) 144 mg 36%
Magtein™ (magnesium L-threonate) 2 g

†Daily value not established.

Other ingredients: gelatin (capsule), silica, and magnesium stearate.

Suggested Use: 3 capsules daily, preferably 2 capsules during the day and 1 capsule 1-2 hours before bed. Start with 1 capsule daily and gradually increase to 3 capsules daily.

NOTE: If you are pregnant, may become pregnant, or breastfeeding, consult your health care professional before using this product.


Do not use if either tamper-evident seal is broken or missing. Keep out of the reach of children.

  • Contains no yeast, dairy, egg, gluten, soy or wheat.
  • Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.

Magtein™ is a trademark of Magceutics, Inc.

Terms and Ingredient Definitions

Source Naturals Magtein Reviews

Summary of Customer Ratings & Reviews

Customer Ratings & Reviews

Magtein 4.5 5 4 4
Seems to have research basis Probably helpful at a reasonable cost. March 31, 2014
Love the product and after two weeks I have noticed a difference already. I will definitely be ordering more of this magtein. February 17, 2014
I switched to this brand because cost seemed lowest for the same main ingredients. October 21, 2013
My senior moments have gone away It is the only magnesium compound that has effectively improved my memory and cognitive functions. July 30, 2013
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