According to the FDA, paid consultants for Young Living Essential Oils promote Thieves Oil to people suffering from specific medical conditions, including viral infections. However, there is no medical proof to support such claims, and the Young Living Products website contains the standard FDA warning that Thieves Oil is not intended to diagnose, treat or prevent any disease.
Young Living Products, the manufacturer of Thieves Oil, claims on its website that, when taken internally, Thieves Oil supports both healthy immune and respiratory system function. However, as noted by the FDA, Young Living Products employs paid consultants to market its products, and many of these consultants have gone so far as to claim that the product can benefit sufferers of Parkinson's disease, various cancers, autism, diabetes and Ebola. These claims have not been verified with the FDA, and in September 2014, Young Living Products received a warning from the FDA outlining several policy violations in relation to the marketing of Thieves Oil.
According to Mayo Clinic, there are no known cures for the common cold. However, staying hydrated and getting enough rest are generally considered the most effective ways to battle cold symptoms, alongside certain over-the-counter products, sipping warm liquids and increasing the amount of moisture in the air.