NOW Testing Reveals Widespread Failures in Vitamin C Gummies Bought on Amazon

NOW Foods has released the results of its latest round of testing of products purchased on Amazon, where, alongside third-party testing lab Alkemist Labs, it found several potency failures in Vitamin C gummies.

 NOW launched a vitamin C gummy in April 2026 after a long search for a stable gummy that would retain potency, and tested two bottles each of 30 gummy supplements alongside Alkemist, which is an ISO 17025-accredited lab, to ensure accuracy and transparency.

NOW included five legacy brands in this round of testing (Mary Ruth’s, Nature’s Way, New Chapter, Nordic Naturals, and Solgar), which passed potency testing with overages. The results showed that 48% of lesser-known brands failed potency testing with nearly no detectable vitamin C, and an additional 16% contained levels that would likely fail before their expiration date because vitamin C degrades in the gummy format.

“After nine years of conducting these rounds of marketplace testing, it is deeply disappointing to still see so many substandard products being sold to consumers,” said Dan Richard, vice president of global sales and marketing.

Vitamin C was quantified with high-performance liquid chromatography (HPLC) using a validated reverse-phase method, NOW reported.

Key Findings

• Out of 25 brands, only 13 met label claim for vitamin C
• 12 of the failing brands had nearly no detectable vitamin C
• Four of the passing brands are likely to fall below their declared amount of vitamin C before their expiration date because vitamin C degrades in the gummy format

Non-specific vitamin C testing methods like spectrophotometric assays can be fooled by other constituents of gummies, such as flavorings or sugars. These methods can inflate potency results, making failing products appear compliant. HPLC separates and identifies vitamin C from closely related compounds, and was used by both NOW and Alkemist Labs.

Stability is also an important consideration when formulating supplements to ensure that the active ingredient remains present at claimed concentrations over the shelf life. Stability studies are time-consuming and expensive, but they show when increases in overage are required in a formula. NOW’s studies suggest that a loss of about 20% per year is possible in vitamin C gummies.

Five brands that claimed to contain 1,000 mg or more vitamin C per gummy, which is unrealistic, had the worst results. These five brands, Ceecisee, Fudualvdel, LiliCare, Neviss, and Vemluta, each contained less than 2 mg, and claimed to be using liposomal forms of vitamin C with unrealistically high amounts of synergistic ingredients.

“It is sad to see such dishonest marketing being used and permitted to fool consumers,” said Richard. “NOW is sharing this report with both the FDA and Amazon, which should take action to remove these ‘bad actors’ from the marketplace.”