Close-up of vitamin supplements, illustrating a laboratory potency test of gummy products

Vitamin C Gummy Tests on Amazon Find Potency Failures

Twelve of 25 vitamin C gummy brands sold on Amazon contained almost no detectable vitamin C when tested by the supplement manufacturer NOW and the independent laboratory Alkemist Labs, according to results published on 20 August 2026 and reported by NutraIngredients. NOW bought samples of 25 marketplace brands it had already flagged as raising labelling questions, purchasing them in June 2026, and quantified ascorbic acid by high performance liquid chromatography using a validated reverse phase method. Thirteen of the 25 met their declared potency at the time of testing. Four of the products that passed were projected to fall below their labelled amount before the end of their stated shelf life. Five brands declaring 1,000mg or more per gummy contained less than 2mg in total, according to the release. Six comparison products from established brands, NOW's own gummy among them, all met their label claims.

Who ran the testing, and why that matters

NOW is a supplement manufacturer rather than a regulator, and it sells vitamin C products that compete with the ones it tested, so this is industry-funded testing and not an independent audit. The analysis itself was run with Alkemist Labs, which holds ISO 17025 accreditation. NOW describes the exercise as its latest round of marketplace testing since the programme began in 2017, and says it has submitted results to Amazon and to the US Food and Drug Administration without action following. Dan Richard, NOW's vice president of global sales and marketing, said: "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."

What this means for your supplement routine

The products were bought on Amazon in the United States, no UK regulator has published an equivalent finding, and this is not a recall, so nothing here names a product on sale in Great Britain or Northern Ireland. What it illustrates is a marketplace problem rather than a supplement problem. The same third-party seller model runs on Amazon's UK site, where unfamiliar brand names sit alongside established ones in the same set of search results. NOW's own figures suggest vitamin C in gummies can decline by around 20 per cent a year, which is one reason a product can meet its label at manufacture and miss it months later. Knowing the brand and the distributor behind a product is the part of this that transfers: every listing in the Perqen catalogue names the brand it comes from.

How Perqen members save

Perqen stocks 1,393 products from established supplement brands, sourced through PowerBody, an authorised EU distributor. Perqen membership costs £4.99 a month or £29.99 a year and unlocks member pricing across that catalogue, with non-members still able to buy at standard prices.

This article reports published news and research and is for information only. Food supplements are not a substitute for a varied diet or medical care, and no product mentioned is intended to diagnose, treat, cure or prevent any disease. Speak to your GP or pharmacist before changing what you take, especially if you are pregnant, breastfeeding, or taking prescribed medicines.

Sources

Originally reported by NutraIngredients. This article has been reviewed by Dr Tosin.

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