The Federal Trade Commission warned three companies on Sept. 10 that they could not legally advertise that their CBD-infused products can “prevent, treat, or cure a human disease without competent and reliable scientific evidence to support such claims.” The companies advertise on their websites and sell oils, tinctures, capsules and other products containing cannabidiol (CBD), a chemical compound derived from the cannabis plant. The FTC did not publicly identify the companies.

One advertiser claimed that its products relieve “even the most agonizing pain” better than opioids do, and that CBD has been “clinically proven,” after thousands of hours with Harvard researchers, to treat cancer, Alzheimer’s disease, multiple sclerosis, fibromyalgia, cigarette addiction, colitis and other diseases.

A second company claimed that its products could successfully treat no fewer than 20 serious illnesses that included, among others, autism, schizophrenia, Parkinson’s disease and other life-threatening afflictions.

The third company made equally expansive claims: that its products could treat the “root cause of most degenerative diseases,” listing, for example, arthritis, cancer and heart disease, and that CBD could alleviate depression, epilepsy and asthma.

The Commission “urged” the companies to review their product claims to ensure they are supported by competent and reliable evidence. It also warned that failure to provide adequate substantiation could violate the FTC Act prohibition on unfair and deceptive advertising and could prompt legal action, possibly resulting in injunctive relief and an order to return money to affected consumers.

The companies have 15 days to respond regarding “the specific actions they take to address the agency’s concerns.”

Tuesday’s warning letters are not the first sign that regulators are scrutinizing claims about the health effects of CBD. The Commission, in conjunction with the Food and Drug Administration (FDA), sent similar letters on April 2, 2019, to Nutra Pure LLC, PotNetwork Holdings Inc., and Advanced Spine and Pain LLC. The FDA has also sent warning letters to other companies making health claims for CBD-infused products, such as a letter to Curaleaf Holdings, Inc., on July 22, 2019, regarding claims that its CBD products relieve “chronic pain” and “chronic anxiety,” and are effective in treating Parkinson’s disease, Alzheimer’s disease, cancer, depression and heart disease.