WASHINGTON — Everyday Advanced Hemp Oil, Bosom Lotion and CBD Edibles Gummie Men may have their fans, but the Food and Drug Administration is not among them.

Four companies selling those and dozens of other marijuana-derived dietary supplements have been warned by the F.D.A. to stop pitching their products as cures for cancer, a common but unproven claim in the industry.

“Substances that contain components of marijuana will be treated like any other products that make unproven claims to shrink cancer tumors,” said Dr. Scott Gottlieb, the agency’s commissioner, in a news release on Wednesday. “We don’t let companies market products that deliberately prey on sick people with baseless claims that their substances can shrink or cure cancer.”

The businesses — Stanley Brothers Social Enterprises, Green Roads of Florida, That’s Natural and Natural Alchemist — each sell products that falsely claim to cure cancer, Alzheimer’s disease or other illnesses, the agency said.