Adulteration to make spinach supplements...stronger?

Spinach extract dietary supplements are sold with the promise of giving health benefits, but may be adulterated with another plant species.

Researchers from the University of Szeged in Hungary describe an unusual situation in which spinach supplements – touted as containing ecdysteroid compounds such as '20E' that promise a non-hormonal anabolic effect and are generally used by body-builders – were found to contain a different plant.

Bizarrely, instead of spinach the supplements contained Cyanotis arachnoidea, a plant native to China which has higher ecdysteroid content. At the time of harvesting the Chinese plant can contain as much as 4 to 5 per cent ecdysteroids, compared to 0.005–0.08 per cent in freshly cut spinach.

"C. arachnoidea and its preparations have not been used in traditional herbal medicines or foodstuffs in Europe and it is unclear whether they can be legally marketed for human consumption, write the authors in the journal Nature Scientific Reports.

In Hungary, they note, high ecdysteroid containing plants are banned by the National Institute for Food and Nutrition Science and so cannot be marketed as food supplements, and the Chinese herb "is neither a foodstuff nor a valued medicinal plant in China."

"This case appears to represent an unusual type of dietary supplement counterfeiting: the alleged pharmacological activities are supposedly enhanced by the addition of extracts from undeclared plants that contain higher amounts of the same active ingredients," they conclude.

"Our results highlight the urgency of in-depth safety studies on Cyanotis extracts" which they say may need to be subject to "proper authorisation."

The supplements under test were sourced from German company VerdeVital.