A testing programme organised by NOW Foods has found that reservatrol supplements available online have fallen short in purity and quality.
The company tested 30 reservatrol supplements purchased on the retail giant Amazon, which have raised 'serious concerns' for their misleading label claims and unexpected contents.
NOW will share the findings with both Amazon and the US Food & Drug Administration (FDA), with the hope the claim will be escalated.
Reservatrol is a polyphenol that is naturally found in grapes, red wine, peanuts and Japanese knotweed roots. It can come in cis or trans form, though trans-reservatrol is higher in bioavailability, and can be easily absorbed by the body.
Misleading label claims seem commonplace
During the testing process, NOW bought two bottles of reservatrol supplements from 30 separate brands, all of which were avaialble through Amazon.com.
According to the company, even before testing, there were a number of products that appeared suspicious; this was due to inflated potency claims and product mislabelling.
After testing the dietary supplements with high-performance liquid chromatography with ultraviolet (HPLC-UV) testing, it was found that:
- 21/30 products tested were below the labelled potency
- Two-thirds of brands had confusing or dishonest labelling for their reservatrol supplements
- 17 products contained less than 10% of the advertised active ingredient
Although this is true, the company stresses there was significant variation between the brands tested in this sample run.
The explicit results of the laboratory analysis can be found through NOW's website.