C in olive oil causes light-dependent toxicity and does not extend lifespan in mice.

C is a potent antioxidant that has been reported to substantially extend the lifespan of rodents when formulated in olive oil (C-OO) or extra virgin olive oil (C60-EVOO). Despite there being no regulated form of C-OO, people have begun obtaining it from online sources and dosing it to themselves or their pets, presumably with the assumption of safety and efficacy. In this study, we obtain C-OO from a sample of online vendors, and find marked discrepancies in appearance, impurity profile, concentration, and activity relative to pristine C-OO formulated in-house.