Celebrity endorsements can wield significant influence over public health decisions, but not all widely shared health claims align with scientific evidence. Several high-profile individuals have promoted wellness trends and medical assertions that have been debunked by experts.
Jenny McCarthy became a prominent voice in the anti-vaccine movement starting in 2005, popularizing the now-discredited claim that childhood vaccines cause autism. McCarthy has stated her belief that her son developed autism after receiving childhood vaccinations, including the MMR shot. However, extensive global studies have found no link between MMR vaccines or vaccines containing thimerosal and autism. Medical experts have described her advocacy as dangerous. While Secretary Robert F. Kennedy Jr. reportedly ordered the CDC to alter its website language regarding vaccines and autism in 2025, the statement "vaccines do not cause autism" remains, accompanied by a note indicating it was placed there "due to an agreement with the chair of the US Senate Health, Education, Labor, and Pensions Committee."
In 2015, Gwyneth Paltrow's wellness brand Goop promoted vaginal steaming, claiming it could balance female hormone levels. While the practice has historical roots in some Asian and African cultures, medical professionals state it has no scientific basis and can be harmful. Dr. Lynette J. Margesson noted that steam typically affects only the vulva and can cause skin scalding, rather than reaching the vagina. Goop also marketed jade yoni eggs, asserting they could enhance sexual energy and balance hormones. Obstetrician-gynecologists warned that the porous nature of jade could harbor bacteria, increasing infection risk. Goop later settled a lawsuit for $145,000 concerning unsubstantiated marketing claims about these eggs.
Kim Kardashian brought attention to celery juice in 2019, influenced by Anthony William, who described himself as a "Medical Medium." William claimed celery juice flushes toxins from the liver, a theory he attributed to a paranormal entity. Kardashian sought it as a treatment for her psoriasis. The National Psoriasis Foundation characterized the celery juice trend as a fad lacking clinical evidence for treating autoimmune diseases. Dr. Abby Van Voorhees stated that celery does not medically improve infections that can trigger psoriasis flares.
In 2025, actor Mel Gibson promoted a combination of ivermectin and fenbendazole as an off-label cancer treatment on a podcast, claiming it cured three friends with Stage 4 cancer. A study published in JAMA reported that prescriptions for ivermectin more than doubled among cancer patients following Gibson's remarks. Researchers expressed concern that individuals with life-threatening illnesses might delay or forgo conventional treatments for unproven therapies. Dr. Skyler B. Johnson noted that while some early studies suggest potential anti-cancer activity in cell and animal models, the dosage required for even a minor effect would likely be toxic to humans.
Actress Shailene Woodley advocated for eating bentonite clay in a 2014 interview, suggesting it binds to negative ions and helps expel heavy metals. She recounted a friend experiencing metallic-smelling bodily waste after consuming it. The practice of consuming clay, known as geophagy, is practiced globally for various reasons, but its safety remains unconfirmed according to a 2022 review. While a "food grade" clay can be processed and tested for safety, it is not necessarily FDA regulated. Craving non-food items like clay, termed pica, can sometimes indicate iron deficiency or other nutrient gaps, particularly during pregnancy, according to registered dietitian Amy Shapiro.