Joseph Michael Mercola (; born July 8, 1954) is an American alternative medicine proponent, osteopathic physician, and Internet business personality. He markets largely unproven dietary supplements and medical devices. On his website, Mercola and colleagues advocate unproven and pseudoscientific alternative health notions including homeopathy and opposition to vaccination. These positions have received persistent criticism. Mercola is a member of several alternative medicine organizations as well as the political advocacy group Association of American Physicians and Surgeons, which promotes scientifically discredited views about medicine and disease. He is the author of two books. Mercola's medical claims have been criticized by the medical, scientific, regulatory, and business communities. A 2006 BusinessWeek editorial stated his marketing practices relied on "slick promotion, clever use of information, and scare tactics". In 2005, 2006, 2011, and 2021 the U.S. Food and Drug Administration (FDA) warned Mercola and his company that they were making illegal claims for their products' ability to detect, prevent, and treat disease. Quackwatch has criticized Mercola for making "unsubstantiated claims [that] clash with those of leading medical and public health organizations and many unsubstantiated recommendations for dietary supplements". Of Mercola's marketing techniques, surgical oncologist David Gorski says it "mixes the boring, sensible health advice with pseudoscientific advice in such a way that it's hard for someone without a medical background to figure out which is which". During the COVID-19 pandemic, Mercola spread misinformation about the virus and pseudoscientific anti-vaccine misinformation on social media platforms. Researchers have identified him as the "chief spreader of coronavirus misinformation online".