Magnesium L-Threonate (Magtein) Supplement

Magnesium is one of the most essential minerals in the body, yet an NIH analysis of NHANES data found that nearly half of American adults fall short of their Estimated Average Requirement through diet alone. Double Wood's Magnesium Glycinate delivers magnesium chelated to glycine, the amino acid that gives this form its name and its gentler digestive profile. This bisglycinate structure protects the mineral from competing ions in the gut, so more of it is absorbed compared to inorganic forms like magnesium oxide or sulfate, supporting muscle recovery and a genuinely relaxed nervous system as the body settles into an evening routine.*

For those building a deliberate wellness routine, Magnesium Glycinate is a natural anchor. It's the foundation of our Phosphatidylserine pairing, built for anyone who feels tired but still wired at the end of a demanding day. Phosphatidylserine supports a healthy stress response while Magnesium Glycinate helps the body and nervous system actually relax. Magnesium Glycinate also pairs well with L-Theanine for those who want a more general mental and physical wind-down.* Every batch is third-party tested by an ISO/IEC 17025 accredited laboratory, and the Certificate of Analysis is published on this page, no request needed.

NSF INDEPENDENTLY CERTIFIED: Double Wood’s Magnesium Glycinate is independently certified by NSF International, a globally recognized third-party organization that verifies label accuracy, ingredient potency, and tests for harmful contaminants, with annual audits to help ensure ongoing compliance.

Soy-Free, Gluten-Free, Non-GMO, Vegan

• Patented by design. Magtein® is the specific, clinically studied form of magnesium L-threonate used in published human research, not a generic magnesium L-threonate alternative.*
• Built for cognitive support. Magtein® has been studied for its role in supporting memory, working memory, and mental clarity as part of a consistent daily routine.*
• Supports deep, restorative sleep. Magnesium L-Threonate has been studied for its role in supporting healthy sleep architecture, including deep and REM sleep stages, as part of an evening routine.*
• Every batch is independently tested and audited to NSF/ANSI 173, with the Certificate of Analysis publicly available.
• Your evening pairing. Magnesium L-Threonate pairs naturally with Apigenin as part of an evening routine, and L-Theanine rounds out a more complete three-part wind-down for those who want it.*

Take 4 capsules daily. Most people split the serving, 2 capsules in the morning and 2 capsules approximately 2 hours before bed. Can be taken with or without food. Those new to Magnesium L-Threonate may prefer starting with 2 capsules for the first week before increasing to the full serving.