Magtein Magnesium L-Threonate 667 mg Source Naturals, 90 Capsules

What Source Naturals Magtein is

Source Naturals Magtein is magnesium L-threonate (also called magnesium threonate) in capsules: each 3-capsule serving has 2 g of Magtein with 147 mg of magnesium, 35% of the Daily Value. The bottle holds 90 capsules of 667 mg, 30 servings. It costs $44.90, about $1.50 a day at 3 capsules (our own math). Free shipping in Puerto Rico on orders from $35, or pick it up at our store in Galería Paseos.

The 667 mg on the front is Magtein per capsule, not magnesium alone. The front says «For learning and memory*». Take 3 capsules daily, preferably split up, starting with 1 a day and increasing gradually.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Its ingredients and what they do in the body

Magnesium, 147 mg per serving (35% of the Daily Value). Magnesium is a mineral the body needs for more than 300 chemical reactions: it helps maintain normal nerve and muscle function and takes part in making energy and protein (MedlinePlus, U.S. National Library of Medicine, “Magnesium in diet”). Most dietary magnesium comes from dark green leafy vegetables; nuts, beans and other legumes, and whole grains are other sources (same source). In this bottle the magnesium comes as magnesium L-threonate and magnesium stearate, according to the label table published by the manufacturer.

Magtein® (magnesium L-threonate), 2 g per serving. It is a salt in which magnesium is bound to L-threonic acid, a compound that plants also make (PubChem, U.S. National Library of Medicine, CID 5460407 and 45489777). Magtein is a registered brand name for this form of magnesium. The label published by the manufacturer links magnesium to cognitive function and brain health, and says that preliminary research suggests this form may provide more magnesium to the brain than other forms.* Each capsule has 667 mg of Magtein; the 3 capsules in a serving add up to 2 g.

What sets it apart:

It is the form that was studied for raising magnesium inside the brain. In a rat study, magnesium L-threonate was the new compound used to raise brain magnesium, and the treated animals did better on learning and memory tests (Slutsky et al., Neuron, 2010, a rat study from the Massachusetts Institute of Technology (PubMed 20152124)). That is a result in animals, not in people or with this bottle, and the study did not measure the 3-capsule serving sold here.

The other ingredients. The capsule is gelatin, so the product is not vegetarian. It also has maltodextrin, magnesium stearate and silica, which help fill the capsule.

These explanations describe normal body functions; they are not results measured with this product.

What the label says

On the front: «For learning and memory*». According to the manufacturer, the side of the label says:

«Magnesium (Mg) plays an essential role in supporting cognitive function and brain health. Preliminary research suggests that MAGTEIN® (magnesium L-threonate) 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. These preclinical findings have now been validated by a clinical study showing positive results in tests of overall cognitive ability after 12 weeks' use of magnesium threonate.*»

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

«Contains no yeast, dairy, egg, gluten, soy or wheat. Contains no preservatives, or artificial color, flavor or fragrance.»

Label facts

The front comes from our bottle; the table, directions, side panel and warnings come from the label with the same code published by the manufacturer (SN2485). The price per day is our own math.

How to take it

Suggested use: 3 capsules daily, preferably in divided doses. Start with 1 capsule daily and gradually increase to 3 capsules daily. At 3 capsules a day, the 90-capsule bottle lasts 30 days (our own math). Store in a cool, dry place.

Warnings

• Caution: Not recommended for use by children or women who are pregnant, may become pregnant, or breastfeeding.
• If you are taking any prescription drugs, 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.

Frequently asked questions

Is the 667 mg magnesium?

No. It is 667 mg of Magtein (magnesium L-threonate) per capsule. The magnesium is 147 mg in the 3 capsules of a serving, 35% of the Daily Value.

What is magnesium L-threonate used for?

The front of the bottle says «For learning and memory*». The label published by the manufacturer says magnesium plays an essential role in supporting cognitive function and brain health.* *These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Where can I buy magnesium threonate in Puerto Rico and what does it cost?

At Borinquen Natural: Source Naturals Magtein, 90 capsules, costs $44.90. Free shipping in Puerto Rico on orders from $35, or pick it up at our store in Galería Paseos.

How do I take it?

3 capsules daily, preferably in divided doses. Start with 1 capsule daily and gradually increase to 3.

How long does the bottle last?

30 days at 3 capsules a day (our own math).

Who should not take it?

The label says it is not recommended for children or women who are pregnant, may become pregnant, or breastfeeding. If you are taking any prescription drugs, consult your health care professional before use.

Is it vegetarian?

No. The capsule is gelatin.

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