A celebrity endorsement can sell a movie, cosmetics and, sometimes, a bogus health claim.
When stars share personal health experiences or opinions, those messages can reach millions of people and spark real-world behavior change.
A 2018 study found that an op-ed penned by Angelina Jolie about her BRCA testing and preventative mastectomy led to a “statistically significant increase” in BRCA testing and mastectomy rates among women who had not been previously diagnosed with breast or ovarian cancer.
But that same reach can amplify claims that conflict with medical evidence or mislead people about their health. From vaccine misinformation to miracle cures, here are five celebrity health claims that needed a reality check rooted in science.
Jenny McCarthy helped popularize the false claim that childhood vaccines causes autism, becoming one of the most recognizable figures in the anti-vaccine movement in the US since 2005.
McCarthy has said she believes her son developed autism shortly after receiving childhood vaccines, including the MMR shot, Children typically receive the MMR vaccine around the same age when autism symptoms would become noticeable, usually between 15 and 18 months as language and social development progress.
Large studies around the world have found no link between MMR vaccines, thimerosal-containing vaccines and autism — and experts have called out her crusade as dangerous.
In fact, autism has no single known cause, and researchers believe multiple factors, like genetics and environmental influences, play a role.
Still, Secretary Robert F. Kennedy, a long-time critic of vaccines, said he ordered the CDC to change the language regarding vaccines and autism on the organization’s website in 2025.
The phrase “vaccines do not cause autism” remains on the website, though, with an asterisk disclaiming that is “due to an agreement with the chair of the US Senate Health, Education, Labor, and Pensions Committee” — Sen. Bill Cassidy (R-La.) — “that it would remain on the CDC website.”
“I’m a doctor who has seen people die from vaccine-preventable diseases,” Cassidy shared on X, regarding the change. “What parents need to hear right now is vaccines for measles, polio, hepatitis B and other childhood diseases are safe and effective and will not cause autism. Any statement to the contrary is wrong, irresponsible, and actively makes Americans sicker.”
#2: Gwyneth Paltrow: Vaginal steaming “balances female hormone levels” and jade eggs “increase sexual energy”
In 2015, Gwyneth Paltrow decided to loop her Goop audience in on her LA spa treatment obsession: vaginal steaming. She described the service as having “a combination of infrared and mugwort steam [that] cleanses your uterus,” offering an “energetic release…that balances female hormone levels.”
The practice has been used in some age-old traditional and indigenous Asian and African cultures, but medical experts don’t advise it — and insist the glorified down-below facial has no scientific basis or benefits.
“The steam almost never gets inside the vagina,” Dr. Lynette J. Margesson told Women’s Health. “Steaming would just affect the vulva and potentially scald the skin.”
A few years later, Goop claimed jade yoni eggs — stones inserted vaginally — lead to pelvic floor gains, “increase sexual energy and pleasure,” balance hormones, regulate menstrual cycles and prevent uterine collapse.
OB-GYNs immediately pointed out that jade is a pretty — but porous — material, making it a prime place for harboring bacteria and increasing the risk of infections like bacterial vaginosis.
Goop ended up settling a lawsuit in 2018 for $145,000 regarding unsubstantiated marketing claims about the egg.
#3: Kim Kardashian: Celery juice flushes toxins and cures psoriasis
Kim Kardashian put celery juice on the map in 2019. On “Keeping Up with the Kardashians,” self-proclaimed “Medical Medium” Anthony William told her the drink flushes toxic copper from the liver, a theory he says comes from a paranormal entity he calls the “Spirit.”
She hoped it would help treat her chronic psoriasis.
“I tried celery juice for eight weeks,” she shared on Poosh, Kourtney’s lifestyle and wellness website. “Then I’d do celery juice mixed with the tea. I would do that twice a day.”
But the National Psoriasis Foundation called the celery juice trend a fad with no solid clinical evidence of treating autoimmune diseases.
“On a medical perspective, celery does not improve the infections in the body that could be triggers for these flares,” said Abby Van Voorhees, MD, NP, NPF Medical Board Chair.
#4: Mel Gibson: Ivermectin cures cancer
In 2025, Mel Gibson sang the praises of a combination ivermectin-fenbendazole regimen as an off-label cancer treatment on the Joe Rogan podcast. He claimed that the drug cured Stage 4 cancer in three of his friends.
“All three of them don’t have cancer right now at all and they had some serious stuff going on,” the actor said.
A study published in JAMA found that prescriptions for the drug more than doubled, jumping over 150% among cancer patients since Gibson’s widely-viewed podcast episode.
That sturge among patients with cancer is particularly concerning to the study authors: “Individuals facing life-threatening illness may delay or forgo conventional treatments in favor of unproven therapies, potentially allowing their disease to progress.”
Dr. Skyler B. Johnson told the Center for Infectious Disease Research and Policy that while some cell and animal studies show that the drugs can produce anti-cancer activity, “the dose needed to have even a small effect would typically be considered toxic for humans.”
#5: Shailene Woodley: Eating clay pulls heavy metals out of your body
In a 2014 interview with Into the Gloss, actress Shailene Woodley praised eating bentonite clay, calling the material “one of the best things you can put in your body.”
She claimed that the clay provides a negative charge that binds to “negative isotropes,” helping to “clean heavy metals out of your body.” “My friend starting eating it and the next day she called me and said, ‘Dude, my shit smells like metal,’” she recalled.
Woodley isn’t alone in her pottery-preferring palate. A recent TikTok trend involved users filling mini clay pots with lime juice, sprinkling them with Tajín and snacking on the earthy bites.
“Craving non-food substances like clay is known as pica, which is sometimes associated with iron deficiency or other nutrient gaps, especially during pregnancy,” Amy Shapiro, a registered dietician and nutritionist, told the Post.
While geophagy — the practice of eating clay as a wellness or spiritual practice — is done globally for a range of wellness and spiritual purposes, the safety has yet to be confirmed, according to a 2022 review.
“There is ‘food grade’ clay that has been processed, purified and tested to be safe for human consumption, unlike other forms of clay,” Dr. Lauren Shawn, a medical toxicologist and emergency medicine physician at Northwell’s Phelps Hospital, told the Post.
“However, even if labeled as food grade, it doesn’t mean it’s FDA regulated.”
