Thorne vs Momentous Magnesium Bisglycinate: same 200 mg, powder or capsules

The two side by side

A $16.99 bottle of the Momentous capsules lasts 30 days⁶. Thorne takes return requests within 60 days of purchase². Prices, terms and NSF listings are as published on October 13, 2026.

Prices are US prices from each maker’s product page or online store, checked on October 13, 2026. They’re before tax and shipping. Where a cell says a figure isn’t stated, we didn’t find it on the pages reviewed.

Which one fits which need

These are picks for different needs, not a ranking. Both give 200 mg of magnesium as magnesium bisglycinate a serving^{1, 5}. So the choice rests on form, price and returns.

• If you want the same dose for less, choose Momentous Magnesium Bisglycinate. A $16.99 bottle lasts 30 days, about $207 a year at two capsules a night⁶. The catch: its refund policy says delivered products generally can’t be returned⁹. The label is also marked vegan, and NSF lists it as free of animal-origin ingredients^{6, 8}.
• If you’d rather drink it, or want a way to send it back, choose Thorne Magnesium Bisglycinate. Thorne takes return requests within 60 days and offers a satisfaction guarantee for a refund or product credit². The catch is cost: $52 a tub, about $316 a year at a scoop a day¹. Approved returns also carry a 25% restocking fee².
• If you’re drug-tested, both have an NSF Certified for Sport listing. NSF lists Thorne’s powder with 21 lot numbers to match against your tub³. It lists Momentous’s capsules for all lots⁸.

What actually differs

Price. Thorne’s tub costs $52 for 60 scoops, about $0.87 a serving¹. Momentous’s bottle costs $16.99 for 30 servings, about $0.57⁶. At one serving a day, that’s about $316 a year against about $207^{1, 6}. Only Momentous shows a subscription price, at $15.29 a bottle after the first delivery^{1, 7}.

Form and other ingredients. Thorne’s powder adds citric acid and monk fruit concentrate, and you mix a scoop into at least 8 oz of water¹. Its badges say “derived from natural flavors” and “derived from natural colors,” though the ingredient list names neither¹. Momentous’s capsules add hypromellose, silica, magnesium stearate and microcrystalline cellulose⁶.

Returns. Thorne takes return requests within 60 days, but approved returns carry a 25% restocking fee². Momentous’s refund policy generally refuses returns of delivered products and doesn’t refund shipping⁹. Neither maker states a warranty^{1, 2, 5, 9}.

The NSF listing. Thorne’s listing gives 21 lot numbers you can match to your tub³. Its 226.2 g package matches 60 scoops, but NSF doesn’t tie the listing to SKU M204³. Momentous’s listing covers all lots of the 60-capsule bottle⁸. Neither shows a certification date^{3, 8}.

Medicine notes. Momentous tells you to check with a doctor first if you take diuretics, antibiotics or bisphosphonates⁵. Thorne’s page says there are no known adverse interactions¹. NIH lists interactions with bisphosphonates, tetracycline and quinolone antibiotics, diuretics and long-term proton pump inhibitors⁴. Its fact sheet doesn’t single out the bisglycinate form⁴.

What stays the same

Both give 200 mg of magnesium as magnesium bisglycinate a serving^{1, 5}. That’s under NIH’s 350 mg adult upper limit for magnesium from supplements and medicines⁴. The limit doesn’t count magnesium from food, but it does count any other magnesium supplement or medicine you take⁴. One serving of either is above NIH’s limit for children aged 1 to 8⁴.

Both makers point you to 30 to 60 minutes before bed^{1, 5}. Both appear in NSF’s Certified for Sport database as unflavored products sold in the United States^{3, 8}. Neither maker names its magnesium supplier or publishes test results on the product page^{1, 5}.

What the labels don’t settle

Both makers market these for sleep. Thorne says its powder promotes restful sleep and muscle relaxation, and its page cites no studies¹. Momentous markets its capsules for sleep and calm and cites published studies, none of them on its product⁵. Both pages say the FDA hasn’t evaluated these statements^{1, 5}.

The closest trial is a 2025 study of 155 adults in Germany who reported poor sleep¹⁰. They took 250 mg of magnesium a day as magnesium bisglycinate, or a placebo, for four weeks¹⁰. Insomnia scores fell 3.9 points with magnesium and 2.3 with placebo¹⁰. That’s a small difference, and it only just reached statistical significance¹⁰. Other sleep, stress and mood measures showed no significant difference¹⁰.

The trial used Biogena capsules, not Thorne’s or Momentous’s product, and sleep was self-reported¹⁰. About 80% of the participants were women¹⁰. An NSF sport listing describes what’s in the container, not what it does. Whether magnesium is worth taking at all is covered in our evidence review.

Sources

1. Magnesium Bisglycinate product page (SKU M204) Thorne · manufacturer
2. Returns and Exchanges Thorne · manufacturer
3. Certified for Sport listing: Thorne Magnesium Bisglycinate NSF · certifier
4. Magnesium: Fact Sheet for Health Professionals NIH Office of Dietary Supplements · regulator
5. Magnesium Bisglycinate 200mg Momentous · manufacturer
6. Magnesium Bisglycinate listing on Momentous's store (price, SKU, weight and label photo descriptions) Momentous · manufacturer · data file
7. Magnesium Bisglycinate listing on Momentous's store (subscription prices and label photo descriptions) Momentous · manufacturer · data file
8. Certified for Sport listing: Magnesium Bisglycinate (Momentous) NSF · certifier
9. Refund policy Momentous · manufacturer
10. Magnesium Bisglycinate Supplementation in Healthy Adults Reporting Poor Sleep: A Randomized, Placebo-Controlled Trial (Schuster et al., Nat Sci Sleep 2025;17:2027-2040) Dove Medical Press, 2025 · randomized trial