Magnesium is involved in over 300 enzymatic reactions, including muscle contraction, nerve signaling, and sleep quality. It is also one of the nutrients most commonly under-consumed when overall food volume drops. People eating smaller meals are at higher risk of running below the recommended 310-420 mg per day, and muscle cramps, poor sleep, and low energy are common early signs of inadequacy.
Momentous and Thorne both produce well-formulated magnesium supplements, but they use different forms of the mineral with different research profiles and intended uses. This comparison helps you choose based on your primary goal — sleep and cognitive function, or general musculoskeletal support and digestion.
Momentous
Momentous Magnesium L-Threonate
Momentous uses Magtein, a patented form of magnesium L-threonate developed at MIT and licensed to supplement manufacturers. L-threonate is one of the few magnesium forms shown in animal studies to cross the blood-brain barrier efficiently, and it is marketed primarily for cognitive performance and sleep quality. Each serving provides 144 mg of elemental magnesium across three capsules.
Pros
- +L-threonate form has human research supporting improvements in sleep quality and cognitive measures
- +Magtein is a standardized, third-party-tested ingredient with published studies
- +Momentous products are NSF Certified for Sport, relevant for anyone in tested sport contexts
Cons
- –Three capsules per serving is a larger pill burden than bisglycinate options
- –Higher cost per serving than most other magnesium forms; elemental magnesium per dollar is relatively low
Thorne
Thorne Magnesium Bisglycinate
Thorne uses magnesium bisglycinate, a chelated form where magnesium is bound to two glycine molecules. Glycine is an amino acid with its own mild calming properties, and bisglycinate is generally well-tolerated with a lower risk of the laxative effect common with magnesium oxide or citrate at higher doses. Each serving provides 200 mg of elemental magnesium in two capsules.
Pros
- +200 mg elemental magnesium per two-capsule serving — one of the higher per-capsule doses in a well-tolerated form
- +Bisglycinate is gentle on the GI tract at standard doses, important when GI sensitivity is already elevated
- +Thorne is a well-regarded brand with NSF certification and a long track record in clinical settings
Cons
- –Less specific evidence for cognitive or sleep outcomes compared to L-threonate; it is a general-purpose magnesium supplement
- –Glycine content is modest; the added calming effect is mild and should not be the primary reason for choosing it
Common questions
What is the best magnesium for sleep on a GLP-1?+
Magnesium L-threonate, specifically the Magtein form, has the most direct research on sleep quality among magnesium forms. Bisglycinate also supports relaxation through its glycine component. Neither is a sleep medication — they support a nutrient that many people eating less are running low on. Discuss ongoing sleep concerns with your clinician.
Does magnesium help with muscle cramps on a GLP-1?+
Muscle cramps can result from low magnesium intake, which becomes more likely when eating fewer calories overall. Magnesium bisglycinate or L-threonate can both help bring intake up to an adequate level. If cramps are frequent or severe, that is worth flagging with your clinician or pharmacist.
Is Thorne or Momentous magnesium better?+
Thorne bisglycinate provides more elemental magnesium per serving at a lower cost and is gentle on digestion. Momentous L-threonate has stronger specific evidence for sleep and cognitive outcomes. The better choice depends on what you are trying to address.
How much magnesium do I need per day?+
The recommended dietary allowance for adults ranges from 310 mg (women) to 420 mg (men) per day from all sources combined. When eating less food, the gap between intake and target widens. A registered dietitian can help you estimate how much you are getting from food before adding a supplement.
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General wellness and nutrition information, not medical advice. We help with nutrition, not medication — talk to your clinician or pharmacist about your medication and routine.