NOW’s Latest Testing of SAM-e Brands on Amazon

NOW’s award-winning quality testing program’s most recent examination, a follow-up survey of SAM-e samples purchased on Amazon in October 2024, demonstrates that profound quality and labeling failings continue.

This is the 19th round of market testing that NOW has performed. As always, the company openly shares these results with Amazon and the FDA hoping they will take action to stop these practices, and with consumers so they can make informed purchases.

NOW previously conducted a survey of suspicious SAM-e (S-adenosylmethionine) supplements purchased on Amazon in March 2020 and found all 11 products tested to be low potency, and two of those brands had zero potency. That was distressing, but not shocking. A lawsuit was filed in 2019 against several similar brands of SAM-e due to low potency, but that was eventually dismissed. (See www.truthinadvertising.org and search for SAM-e).

NOW chose to investigate SAM-e for a second time because the product is expensive, and brands appear to cheat regularly with costly products such as SAM-e. In this reexamination of the SAM-e category, NOW decided to gather a new round of samples from more brands and see if any brands corrected their false labeling claims. In October 2024, NOW purchased two bottles each of 24 suspicious SAM-e supplements on Amazon to test internally and externally at Eurofins labs. Some brands were chosen because they appeared to be mislabeled based on excessively high potency claims. NOW chose several in the gummy format, because SAM-e is unstable and can degrade quickly due to moisture and heat.

Because SAM-e is an unstable compound it is often enteric-coated to maintain stability. Ingredient supplier Gnosis by Lesaffre also makes a proprietary SAM-e from disulfate tosylate salt that is stable enough to avoid enteric coating. SAM-e potency is somewhat confusing to understand. It takes a minimum of 800 mg of S-Adenosyl L-Methionine Tosylate Disulfate to produce 400 mg SAM-e (S-Adenosyl L-Methionine). Some brands label full disclosure to include this, while others do not. It is not required but does help consumers fully understand what is in the product.

The chart below shows five repeat low-potency brands that continue to be widely sold on Amazon. Note that 48% of failing samples were found in Florida-based brands with some sharing matching or near-identical lot numbers. All samples were tested by High-Performance Liquid Chromatography (HPLC) at both NOW’s and Eurofins’ labs using a validated method for testing SAM-e based on the USP monograph for SAM-e. 

Here are some conclusions:

• NOW’s product tested well above the label claim at 109% average. NOW adds significant overages to ensure full potency at expiration date. 
• 20 of the remaining 23 samples failed potency testing (highlighted red in the table), and 16 of the remaining 23 brands contained less than 20% of labeled potency! Six brands contained ZERO potency at all, including both Gummy products.
• The five brands that failed testing in 2020 (highlighted yellow in the table) failed again, with one containing zero potency and three containing less than 20% of label claim.  Repeated failures include aSquared, Healthy Way, Mono Herbs, Nasa B’Ahava, and Superior Health. Mono Herbs tested at zero potency for the second time in four years.
• Ojos Labs and Shevat Vitamins are located in Florida, and their samples share the same lot number. Both, likely made by the same manufacturer, contained less than 10% potency.
• aSquared brand is a repeat potency failure. In the past six years, NOW has tested 13 different lots of different products by aSquared, and every single product tested failed potency testing. This product was below 20% potency.
• The Natures Craft and Phytoral brands also had nearly identical lot numbers. Both tested below label claims on average but were close to full potency.
• The Spliferkou brand makes ridiculous potency claims. This product title claims to include an impossible 3,000 mg, and that is before doubling the SAM-e potency input needed to reach 1800 mg claim. Typically, large double 00 capsules can include a maximum of 1,000 mg, while adding up the claimed ingredients alone nets 2,350 mg per capsule. There is no physical way to reach the levels claimed for this product. Not surprisingly, this brand tested with zero SAM-e potency.
• One brand labeled in vegetarian capsules tested to contain animal gelatin. This was Florida Herbal Pharmacy, which also failed with zero potency.