How we choose third-party tested supplements

What earns a place

This guide covers supplements sold to US buyers at a published price on the maker’s own site or store. Each must also appear in an independent certifier’s own database. A seal on the maker’s page isn’t enough on its own.

The current eleven start with two creatine powders, Thorne Creatine and Momentous Creatine, and two fish oils, Nordic Naturals Ultimate Omega 2X Sport and Momentous Omega-3. Next come two vitamin D3 products, Thorne Vitamin D-5,000 and Nordic Naturals Vitamin D3 Gummies Sport, and two whey isolates from Thorne and Momentous. Two are magnesium bisglycinates: Momentous’s capsules and Thorne’s powder. The eleventh is Momentous Daily Hydration, an electrolyte drink mix. One-time prices ran from $16.99 to $69.99 a container on October 13, 2026^{5, 7, 9–12, 14, 28, 30, 36, 38}.

We start from a certifier listing for a reason. FDA doesn’t have the authority to approve dietary supplements before they’re marketed, and it doesn’t test them before they’re sold to consumers². Manufacturers and distributors have the initial responsibility for making sure their products meet safety standards². All eleven products appear in NSF’s Certified for Sport database^{3, 4, 15, 23–26, 29, 31, 35, 37, 39}.

Each pick names the need it serves, its trade-off and an alternative. Picks are for different needs, not a ranking. A product you can’t order on the maker’s own page keeps its review but doesn’t get a pick or an alternative slot. Whether to take a supplement at all is a separate question, and our evidence review covers it.

What we weigh

Seven questions decide the picks. Each answer comes from the maker’s page, online store or policy, a certifier’s database, a government fact sheet, or a named study or news report. We record the date each one was checked.

• A listing for the product, in the certifier’s own database. A seal on a product page isn’t enough, so we look the product up in NSF’s database. We record the form, serving size, package sizes and lot numbers it shows. Thorne Creatine’s listing gives 66 certified lot numbers³. Momentous Creatine has two entries: one for the 450 g jar with 24 lot numbers, and one covering four sizes with lot “All”^{4, 35}. NSF says its mark means the contents match the label, with none of 290 substances banned by major athletic organizations and no unsafe levels of contaminants¹. The product must also be made at a GMP-certified facility that NSF audits annually or bi-annually, depending on its grade¹. So “made in an NSF-certified facility” describes only the factory, and we don’t count it as a product certification.
• Form and elemental dose, against NIH’s limits. We record the amount of the nutrient itself. Momentous Magnesium Bisglycinate gives 200 mg of elemental magnesium as magnesium bisglycinate per two capsules^{27, 28}. Thorne’s powder gives the same 200 mg in one scoop³⁶. NIH’s upper limit for magnesium from supplements and medicines is 350 mg a day³². For vitamin D, NIH lists an adult upper limit of 4,000 IU (100 mcg) a day²⁰. The adult RDA is 600 IU through age 70 and 800 IU after that²⁰. Thorne’s Vitamin D-5,000 supplies 5,000 IU a capsule, so we treat it as a strength for clinician-advised use¹¹. The Nordic Naturals gummy supplies 1,000 IU¹². For an electrolyte mix, we record the minerals per packet. A Daily Hydration packet has 100 mg of sodium and 50 mg of potassium³⁸.
• For fish oil, EPA and DHA in milligrams. We record EPA and DHA per serving, not total fish oil. Two Momentous softgels give 800 mg of each³⁴. Two Nordic Naturals softgels give 1,125 mg EPA and 875 mg DHA²². A 2021 meta-analysis pooled seven cardiovascular-outcome trials²¹. The rise in atrial fibrillation risk was larger in trials testing more than 1 g a day (hazard ratio 1.49) than at 1 g or less (1.12)²¹. So a bigger dose doesn’t score better.
• What else is in the serving. Sugar, sweeteners, gelatin, fish and milk all matter to someone. Each vitamin D3 gummy carries 2 g of sugar¹³. Thorne’s whey isolate is derived from milk and lists evaporated cane juice sugar and stevia¹⁴. Momentous’s Chocolate whey isolate is sweetened with monk fruit extract and stevia instead³⁰. Thorne’s magnesium powder adds citric acid and monk fruit concentrate³⁶. Every Daily Hydration label lists organic cane sugar and organic honey powder, for 1 g of total sugars a packet³⁸. Even so, NSF’s Grapefruit listing types it as vegan and free of ingredients of animal origin³⁹.
• Lead in protein powder. Supplements have no federal limit on heavy metals, NPR reported in October 2025³³. Consumer Reports had tested 23 protein powders and ready-to-drink shakes³³. More than two-thirds had more lead in one serving than CR’s 0.5 mcg daily level of concern, which is based on California’s Proposition 65³³. Plant-based powders averaged nine times the lead of dairy-protein powders³³. Both proteins in this guide are whey^{14, 30}. Thorne’s page carries a Proposition 65 lead warning but gives no amount¹⁴.
• What a year costs. A container price says little on its own. At the label dose, a $39.99 bottle of Momentous Omega-3 lasts 30 days, while a $44 tub of Thorne Creatine lasts 90^{5, 10}. The two magnesium products give the same 200 mg a day^{28, 36}. Thorne’s $52 tub lasts 60 days, and Momentous’s $16.99 bottle lasts 30^{28, 36}. So we compare a year at the label dose and the one-time price, as described under How prices are checked.
• What you can get back. Thorne takes return requests within 60 days of purchase, but all approved returns carry a 25% restocking fee¹⁶. Nordic Naturals takes back unmarked, resalable products bought directly from it within 30 days of receipt¹⁷. It also offers a separate 60-day satisfaction guarantee¹⁸. Momentous’s refund policy says it generally doesn’t accept returns of delivered products, except where the law requires it¹⁹.

What we don’t weigh

Benefit statements on product pages don’t move a product up or down. FDA generally doesn’t approve dietary supplement claims or other labeling before use². The pages reviewed make statements about muscle, brain, heart, bone, immune function or mood that their makers say FDA hasn’t evaluated^{5, 9, 11}. Momentous markets its magnesium for sleep and calm, and its page carries the same FDA notice²⁷. Thorne says its magnesium powder promotes restful sleep, and its page cites no studies³⁶.

We also set aside dose and purity claims without published methods. Momentous calls 1,600 mg of EPA and DHA a clinically effective dose³⁴. It also says its creatine shows 99.8% potency accuracy, without showing a certificate of analysis⁶. Neither claim was checked independently.

Certifications we couldn’t confirm are recorded as the maker’s claim, not as a pass. Momentous says its Omega-3 is IFOS certified¹⁰. Nordic Naturals says its fish oils are Friend of the Sea certified and third-party tested⁹. Neither claim was checked in that program’s own listings.

We don’t rank by lot counts either. A list of 66 lots and a listing for all lots both place a product in NSF’s program^{3, 4}. Neither shows a certification date^{3, 4}.

Everything on NSF’s list concerns a product’s contents and how it’s made¹. None of it covers whether the supplement has a health effect¹. What trials show for creatine, fish oil, vitamin D and magnesium is in our evidence review, not in these picks.

How facts are checked

Every fact in a product review cites the page it came from and the date it was checked. When a maker’s page, a certifier and a retailer disagree, we record each version rather than picking one. Thorne’s whey isolate page gives 21 g of protein in its headline but lists 25 g of whey protein isolate in its supplement facts¹⁴. NSF’s listing gives 21 g¹⁵. Momentous’s Daily Hydration labels give 1 g of total sugars a packet, but one product image says 2 g³⁸.

Sometimes the match between a product and its listing rests on details, and we say so. NSF lists Momentous’s chocolate whey as “Essential Grass Fed-Whey Protein Chocolate,” a name Momentous’s page doesn’t use^{30, 31}. The match rests on the brand, the flavor, the store’s web address and a 655 g package that equals 25 scoops of 26.2 g^{30, 31}. NSF’s listing for Thorne’s magnesium gives a 226.2 g package, which equals 60 scoops of 3.77 g, but it doesn’t name the SKU³⁷.

Some counts aren’t on the maker’s product page, so we say where they came from. Nordic Naturals’ page doesn’t say how many gummies its $23.95 bottle holds, so the 120 behind the yearly cost comes from Fullscript and NSF^{12, 13, 26}. Momentous’s magnesium page doesn’t show the capsule count either²⁷. The 60-capsule count comes from the descriptions of the label photos on Momentous’s online store²⁸.

Some products have more than one NSF entry. Momentous Creatine’s 450 g entry carries the vegan claim shown on Momentous’s page, so we treat it as the match^{6, 35}. A second Momentous entry lists four package sizes for all lots, and NSF doesn’t say how the two relate⁴.

When a maker’s page doesn’t show the full label, we read it from another listing and name that listing. The Supplement Facts for both Nordic Naturals products come from Fullscript’s listings, not from nordic.com^{13, 22}. When a maker doesn’t state a figure, we record it as not stated and don’t guess. Thorne doesn’t give the net weight of its creatine or its magnesium powder^{5, 36}. Neither vitamin D maker names the source of its D3^11–13.

How prices are checked

Prices are US one-time prices for the exact size, before tax and shipping, from the maker’s official page or online store on the check date. Subscription and first-delivery prices are noted but not used. Momentous’s creatine page shows a “25% Off” badge⁶. Its Subscribe & Save prices show that discount covers only the first delivery, $32.24, with later deliveries at $38.69⁸. So the review uses the $42.99 one-time price from Momentous’s online store⁷.

The same pattern shows up elsewhere. Momentous’s whey page shows “$2.09/serving,” close to the first Subscribe price of $52.49 for 25 servings³⁰. The one-time price is $69.99, about $2.80 a serving³⁰. Nordic Naturals lists a 10% Subscribe & Save price of $50.36 beside the $55.95 Buy Once price for Ultimate Omega 2X Sport⁹. Momentous’s Daily Hydration page showed struck-through prices that don’t match its store listing, so the review uses the listing’s $24.99^{38, 40}.

A year’s cost is the one-time price times the containers needed at the label dose. Thorne Creatine’s 90 daily servings at $44 work out to $178.44 a year⁵. Nordic Naturals’ Ultimate Omega 2X Sport, a 30-day bottle at two softgels a day, comes to $680.73 a year⁹. Where the directions say “as needed,” as Momentous’s whey page does, we assume one serving a day and say so³⁰. Momentous suggests multiple Daily Hydration packets a day but gives no number, so we use one, about $304 a year³⁸.

A price you can’t pay is recorded but flagged. Nordic Naturals’ gummy page listed $23.95 but had no Add to Cart button on October 13, 2026¹². Its review keeps that list price for the yearly cost and says you couldn’t order it there. That’s also why the gummies aren’t a pick or an alternative.

The three-year estimate adds the first container to three years of refills. That’s about one container more than three years of daily servings would need. Tax and shipping are left out, and an unknown cost is never counted as zero.

What we don’t do

These limits apply to every supplement review and pick.

• We don’t give scores, star ratings or a single overall winner.
• We don’t give medical or dosing advice. Doses are reported against the label and NIH reference values. Whether and how much to take is a decision for a clinician, especially above an upper limit or alongside medicines. For vitamin D, NIH names statins, steroids and thiazide diuretics among the medicines that can interact²⁰. For magnesium, it names oral bisphosphonates, some antibiotics, diuretics and long-term proton pump inhibitors³².
• We don’t repeat disease, treatment or cure claims, or treat a product page’s benefit statements as evidence.
• We don’t present a subscription, first-delivery or member price as a list price, or count an unknown cost as zero.

Sources

1. What Our Mark Means NSF Certified for Sport · certifier
2. Questions and Answers on Dietary Supplements US Food and Drug Administration · regulator
3. Certified for Sport listing: Thorne Creatine NSF · certifier
4. Certified for Sport listing: Creatine Monohydrate (Momentous) NSF · certifier
5. Creatine - 90 Servings (SF903) Thorne · manufacturer
6. Creatine (Creapure creatine monohydrate) Momentous · manufacturer
7. Creatine - 90 Servings store listing (variant price and SKU) Momentous · manufacturer · data file
8. Creatine - 90 Servings store listing (Subscribe & Save plan prices) Momentous · manufacturer · data file
9. Ultimate Omega 2X Sport Nordic Naturals · manufacturer
10. Omega-3 Fish Oil Supplement (60 Capsules) product page Momentous · manufacturer
11. Vitamin D-5,000 - NSF Certified for Sport - 60 Servings (D138) Thorne · manufacturer
12. Vitamin D3 Gummies Sport Nordic Naturals · manufacturer
13. Vitamin D3 Gummies Sport (120 Gummies), Nordic Naturals Fullscript
14. Whey Protein Isolate - Vanilla (SP111) Thorne · manufacturer
15. Certified for Sport listing: Thorne Whey Protein Isolate Vanilla Flavored NSF · certifier
16. Returns and Exchanges Thorne · manufacturer
17. Returns Nordic Naturals · manufacturer
18. Satisfaction Guarantee Nordic Naturals · manufacturer
19. Refund policy Momentous · manufacturer
20. Vitamin D: Fact Sheet for Health Professionals NIH Office of Dietary Supplements · regulator
21. Effect of Long-Term Marine Omega-3 Fatty Acids Supplementation on the Risk of Atrial Fibrillation in Randomized Controlled Trials of Cardiovascular Outcomes: A Systematic Review and Meta-Analysis (Gencer et al.) Circulation, 2021 · meta-analysis
22. Ultimate Omega 2X Sport (60 Softgels), Nordic Naturals Fullscript
23. Ultimate Omega 2X Sport (NUS-01807) - Certified for Sport listing NSF · certifier
24. Momentous Omega-3 - Certified for Sport listing NSF · certifier
25. Certified for Sport listing: Thorne D-5,000 NSF · certifier
26. Vitamin D3 Gummies Sport (RUS-31142) - Certified for Sport listing NSF · certifier
27. Magnesium Bisglycinate 200mg Momentous · manufacturer
28. Magnesium Bisglycinate listing on Momentous's store (price, SKU, weight and label photo descriptions) Momentous · manufacturer · data file
29. Certified for Sport listing: Magnesium Bisglycinate (Momentous) NSF · certifier
30. Grass-Fed Whey Protein Isolate Powder (Whey Protein Isolate) Momentous · manufacturer
31. Certified for Sport listing: Essential Grass Fed-Whey Protein Chocolate (Momentous) NSF · certifier
32. Magnesium: Fact Sheet for Health Professionals NIH Office of Dietary Supplements · regulator
33. A study found lead in popular protein powders. Here's why you shouldn't panic NPR (via OPB), 2025 · news
34. Omega-3 listing on Momentous's store (price and label photo descriptions) Momentous · manufacturer · data file
35. Certified for Sport listing: Creatine Monohydrate, 450 g (Momentous) NSF · certifier
36. Magnesium Bisglycinate product page (SKU M204) Thorne · manufacturer
37. Certified for Sport listing: Thorne Magnesium Bisglycinate NSF · certifier
38. Daily Hydration listing on Momentous's store (prices by flavor, SKUs, weights and label photo descriptions) Momentous · manufacturer · data file
39. Certified for Sport listing: Daily Hydration, Grapefruit Flavor (Momentous) NSF · certifier
40. Daily Hydration Electrolyte Powder Momentous · manufacturer