Dr. Mark Hyman, a “functional medicine” proponent and longtime friend of Robert F. Kennedy Jr., is finding powerful allies in his bid to treat disease with blood tests and supplements.. Dr. Mark Hyman didn’t hesitate before accepting an invitation, 14 years ago, to a weeklong white-water rafting trip with Robert F. Kennedy Jr.. Mr. Kennedy, the environmental lawyer, conspiracy theorist and political scion, was bringing like-minded souls to the wild, undammed Futaleufú River in southern Chile to raise awareness about a hydropower project threatening the valley. Dr. Hyman was exactly the type of expert Mr. Kennedy forged alliances with: a doctor who bucked the mainstream and had a roster of well-heeled clients.. At one point on the trip, Dr. Hyman recalled, his raft overturned, and he clung to it until the group reached calmer waters. Later, on shore, he and Mr. Kennedy indulged in a gaucho-style barbecue. “It’sa dangerous river,” Dr. Hyman said in a recent interview with The New York Times. “We survived that experience together.”. The two men have bonded on many other getaways in the years since, often discussing Dr. Hyman’s preventative approach to health care, known as functional medicine. As their connection grew, so did their fame.. Dr. Hyman, 65, has amassed millions of followers interested in his booming wellness empire, which includes a supplement company, a hit podcast, 15 best-selling books and a start-up health testing company with celebrity backing.. And the doctor’s adventure partner, Mr. Kennedy, ascended to become an independent presidential candidate and, now, President-elect Donald Trump’s pick for the next secretary of Health and Human Services, vowing to “Make America Healthy Again.”. Image. Robert F. Kennedy Jr., left, with Dr. Hyman during a 2010 white-water rafting trip to southern Chile.Credit…via Mark Hyman. Both men have promoted unfounded ideas, including the notion that certain vaccines may be linked to autism. But the principles of functional medicine — spotting problems early, ferreting out their “root causes” and treating them with food and supplements — have been enthusiastically received, not only by an American public distrustful of medical authorities, but also by prestigious hospitals eager to capitalize on the trend.. A growing number of doctors agree that American medicine has for too long snubbed preventative care, to the detriment of patients. But critics are skeptical of Dr. Hyman’s solutions, which include unproven approaches like ozone therapy and heavy metal detoxification.. His ideas could soon be peppered into federal health policy. Mr. Kennedy has said that he would like to see an end to what he sees as the government’s “suppression” of supplements and exercise, and he supports greater insurance coverage for diagnostic tests. Dr. Mehmet Oz, who was chosen by Mr. Trump to oversee Medicare and Medicaid, once hosted Mr. Kennedy and Dr. Hyman on his popular television show, discussing the potential dangers of mercury in certain vaccines.. Dr. Hyman considers himself politically independent, and he has said he sees Mr. Trump’s embrace of Mr. Kennedy, a former Democrat, as a bipartisan opportunity to help the record number of Americans struggling with obesity, diabetes and heart disease.. “Whether you like their politics or not, there’s a conversation happening that this is killing us,” Dr. Hyman said. “People are disillusioned with our traditional health care system.”. Mercury and Vitamin C. Image. Linus Pauling, a two-time Nobel Prize-winning chemist, pictured in 1967. He recommended that some people might benefit from up to five grams a day of vitamin C.Credit…Universal History Archive/Universal Images Group, via Getty Images. From his first day of medical school at the University of Ottawa in the 1980s, Dr. Hyman said, he felt that he was being brainwashed. The school’s disease-centric approach lined the pockets of the health care industry without addressing underlying issues like diet and exercise, he thought.. After graduating, Dr. Hyman began to work as a family physician in rural Idaho, where he saw “a never-ending train of sick patients who shouldn’t be sick,” he said. By his mid-30s, after spending a year working in China, he found himself similarly suffering from an unexplainable constellation of symptoms, including fatigue, brain fog and food allergies.. “My whole system broke down,” he recalled. His own visits to doctors to find a cause proved unfruitful.. In 1996, he started a new job as a medical director at Canyon Ranch, a wellness retreat and spa in Lenox, Mass. It was there that he first became curious about the budding field of functional medicine, he said, which he hoped might offer a solution to his problems.. The field’s origins trace to Linus Pauling, a two-time Nobel Prize-winning chemist who in 1970 recommended that some people might benefit from up to five grams a day of vitamin C — more than 100 times the amount needed to prevent a deficiency. Pauling later promoted vitamin C’s promise in prolonging the lives of cancer patients and treating H.I.V., among other dubious theories.. At a conference in Boston in 1997, Dr. Hyman met one of Pauling’s disciples, the biochemist Jeffrey Bland, who sold supplements, published a journal and held seminars on ways to integrate insights from massage therapists, acupuncturists and dietitians into a more personalized practice of medicine.. The pair hit it off, and Dr. Hyman took a course by Dr. Bland. “I listened to him and was like, ‘Either this guy’s full of bullshit or he’s a genius,’” Dr. Hyman said.. Following Dr. Bland’s counsel, Dr. Hyman underwent extensive testing and concluded that his illness arose partly from exposure to mercury pollution in China and stress from a recent divorce. After changing his diet, taking saunas daily and undergoing chelation therapy to remove lead and mercury from his blood, he said, he began to feel better.. In 2004, Dr. Hyman founded his own practice, the UltraWellness Center, also in Lenox, and began selling supplements, including Dr. Bland’s, through a company he started, Vitamin Portfolio. He recommended, among other things, high doses of vitamin C, arguing that it helped reduce lead levels in the blood.. He swiftly rose to become one of the country’s most prominent alternative medicine practitioners, connecting with broad audiences by sharing his personal story of illness and recovery through appearances on “The Dr. Oz Show” and a collaboration with Rick Warren, the megachurch pastor who incorporated wellness into his sermons. Former President Bill Clinton even became his patient after a quadruple bypass surgery, adding fish and lean meats to his otherwise vegan diet on Dr. Hyman’s advice. (Reaping the benefits of a plant-rich, paleo diet became the topic of Dr. Hyman’s best-selling book “The Pegan Diet.”). In 2023, Dr. Hyman’s combined businesses brought in $28.8 million in revenue, he said, and his supplement company alone has 300,000 customers.. While experts agree that exposures to heavy metals, pesticide residues and hormone-disrupting chemicals can increase the risk of chronic illnesses, the functional medicine approach of repeatedly testing and treating these exposures is unproven — “reams of useless tests in one hand, a huge invoice in the other,” as one influential critic, Dr. David Gorski, put it.. “It’s pretty much an unregulated space,” said Dr. Dariush Mozaffarian, a cardiologist at Tufts University in Boston. “You have doctors who are doing their best and are working really hard to use all their wisdom and knowledge to do their best for patients, and others who just want to make a buck.”. Image. The Canyon Ranch spa and wellness center in 2017. Dr. Hyman became curious about the budding field of functional medicine while he served as the center’s medical director.Credit…Lauren Lancaster for The New York Times. Vaccine Concerns. Dr. Hyman said he first met Mr. Kennedy in 2009, shortly after giving a talk about environmental toxins in New York City’s West Village. In the audience was Mr. Kennedy’s wife at the time, Mary Richardson Kennedy.. After Dr. Hyman’s talk, Ms. Kennedy approached him and suggested he meet her husband at their home in Westchester County. Around that time, Mr. Kennedy received chelation therapy because of high mercury levels in his blood, which he attributed to a fish-heavy diet.. Dr. Hyman soon joined Mr. Kennedy and his environmental organization, Waterkeeper Alliance, on the harrowing rafting trip in Chile, which was followed by similar adventures to Machu Picchu and the Green River in Utah. Dr. Hyman also regularly visited the Kennedy family compound in Hyannis Port, Mass., where he said he hand-fed Mr. Kennedy’s enthusiastic pet emu.. In 2014, Dr. Hyman helped Mr. Kennedy research his book about thimerosal, a form of mercury used as a preservative in some vaccines.. Years earlier, Dr. Hyman had published an article in the journal Alternative Therapies in Health and Medicine, where he served as editor in chief, describing a 2-year-old who was diagnosed with autism shortly after receiving the standard suite of childhood vaccines. Dr. Hyman said that the boy also had high levels of mercury in his body.. By that time, a British study that had popularized the idea that vaccines might cause autism had been largely discredited. Nevertheless, Dr. Hyman wrote in the article that certain children were unable to “handle” the measles, mumps and rubella vaccine. The boy saw “dramatic” improvements, Dr. Hyman wrote, within a few weeks of taking supplements and probiotics and avoiding gluten. Later, he received chelation therapy.. In the preface of Mr. Kennedy’s book, Dr. Hyman wrote that while he was generally pro-vaccine, there was room to debate whether mercury, once widely used as a preservative in vaccines, was a factor in the rising cases of autism. (Thimerosal was never part of the MMR vaccine, and it was removed from required childhood vaccines in the U.S. in 2001. It remains in the multidose vial formulations of the flu vaccine.). The two men traveled to Washington, D.C., together a few months before Mr. Kennedy’s book was published to raise their concerns with vaccine officials at the Food and Drug Administration, the Centers for Disease Control and Prevention and other health agencies.. Dr. Hyman told The Times that he was not singling out vaccines but was noting that they represent one more risk factor that might contribute to autism and other disorders.. “These kids are like the yellow canaries in our society,” he said. “The genes load the gun, and the environment pulls the trigger.”. Image. Robert F. Kennedy Jr., campaigning against childhood vaccine mandates at a rally in Albany in 2019.Credit…Desiree Rios for The New York Times. Going Mainstream. Dr. Hyman may have associated himself with disputed ideas, but by 2014, his movement was gaining mainstream acceptance. That year, the Cleveland Clinic in Ohio tapped him as the founding director of its Center for Functional Medicine, the first of its kind at a prestigious academic medical center.. “This helped establish my credibility to study the effects of heavy metals and toxins,” Dr. Hyman said.. He raised $20 million for research on functional medicine and his team earned media attention for using chelation therapy to treat former Army Special Forces members suffering from lead poisoning. They later expanded heavy metal testing for conditions as diverse as diabetes and chronic fatigue syndrome.. Those programs, Dr. Hyman said, helped him and Mr. Kennedy raise awareness about toxic exposures through Mr. Kennedy’s nonprofit organization, the World Mercury Project, which would be renamed Children’s Health Defense in 2017.. The Cleveland Clinic’s functional medicine center deployed extensive testing and encouraged food and lifestyle changes to treat chronic conditions. Patients saw a registered dietitian and health coach during their initial visit, for example. In 2019, a study led by the center’s researchers found that its patients reported greater improvements in their physical health after a year than did those who visited the clinic’s traditional primary-care facility.. Dr. Miguel Regueiro, a gastroenterologist who has shared patients with Dr. Hyman, said the program had been particularly helpful for patients with inflammatory bowel disease and other chronic conditions.. Not everyone has come away with such glowing reviews.. A patient named Abby said her primary care doctor at the Cleveland Clinic referred her to the functional medicine center in November 2021, when she was dealing with shortness of breath, joint pain and fatigue after successful treatment for thyroid cancer.. The center tested her for Lyme disease and other conditions, for which her insurance was billed $4,925, according to medical records she shared with The Times. Abby’s doctor at the clinic gave her a referral code to order vitamins from Dr. Hyman’s company, which shared a percentage of its sales revenue with the hospital. The doctor also recommended Gregorian chanting and forest bathing.. None of these alternative treatments worked, said Abby, who did not want to share her last name for privacy reasons. A rheumatologist at the Cleveland Cliniclater diagnosed her with an autoimmune disease and put her on a prescription medicine, which she said improved her joint pain and fatigue.. A representative for the Cleveland Clinic declined to comment on Abby’s case because of privacy considerations, but said that Abby’s treating physician was no longer at the center.. Dr. Hyman is no longer the center’s director. Dr. James E. Carter, a cardiologist who took over that job, said that blood and urine testing could help identify nutritional deficiencies and other problems, but that he pursues that path only after meeting with a patient and determining that it is medically necessary.. “There are some practitioners who are likely pushing the envelope,” Dr. Carter said. “I don’t believe in that, and we don’t do that in the program.”. Image. Dr. Hyman has detailed his views on food’s role in revolutionizing health care in multiple best-selling books. Credit…Damon Winter/The New York Times. ‘It Shouldn’t Be Called the F.D.A., Bobby’. In March 2021, Dr. Hyman invited a dozen friends to a beach house in Maui. In between hiking, yoga and Himalayan Tartary buckwheat pancakes, he and Jonathan Swerdlin, a venture capitalist, discussed how they might fix what they viewed as a broken health care system.. They fleshed out plans for a company that would allow people to monitor biological changes in their own body. The company, Function Health, would come to be backed by the actors Matt Damon and Zac Efron, along with the investor Marc Andreessen.. It was through Mr. Swerdlin, Function’s chief executive, that Dr. Hyman methis wife, Brianna Bella-Hyman, who now oversees Dr. Hyman’s business portfolio. Dr. Hyman’s two children from a previous marriage are following in their father’s footsteps: His son is a health-conscious chef and founder of a biohacking spa, while his daughter is in medical school.. Function offers customers a suite of blood and urine tests for an annual fee of $499. More than 100,000 people have signed up for the service so far, with another 400,000 on a waiting list. Function Health’s testing costs, Dr. Hyman said, are a fraction of what a typical doctor’s office would charge.. “There’s a pent-up demand for people wanting to find a different way to deal with chronic diseases,” Dr. Hyman said.. He said that he and Mr. Kennedy had often spoken about the need for greater insurance coverage of such diagnostics to tackle the chronic disease crisis. “This should be declared a national emergency,” he said.. In an episode of Dr. Hyman’s podcast in January, when Mr. Kennedy was running for president, the two men raised doubts about the integrity of the nation’s scientific and regulatory institutions.. “It shouldn’t be called the F.D.A., Bobby,” Dr. Hyman said, noting that the agency spent most of its $6 billion budget on drugs, not food and nutrition.. In the same interview, Mr. Kennedy said that, if elected president, he would have federal research agencies investigate the role of environmental exposures, vaccines and diet on autism and obesity. Mr. Kennedy also chastised scientific publishers for being too cozy with the food and pharmaceutical industries.. “I’m going to call in all the scientific journals into the Justice Department,” he told Dr. Hyman, to tell them, “‘You are lying to the public and you’ve caused tremendous damage to public health.’”. Six months later, shortly before Mr. Kennedy dropped out of the race and endorsed Mr. Trump, Dr. Hyman was surprised to see a photograph taken during their Chilean rafting trip published on Vanity Fair’s website. In the photo, Mr. Kennedy is seen posing with an animal carcass on a barbecue spit.. Mr. Kennedy had reportedly sent a text message to a friend suggesting that the animal was a dog, which the magazine portrayed as likely, backed by the opinion of a veterinarian.. The text message was a joke, just Bobby being Bobby, Dr. Hyman said. As for the animal? It was actually an essential part of his “pegan” diet: grass-fed Patagonian lamb.. “I can confirm that news story was nonsense — yet another example of the media trying to discredit him,” Dr. Hyman said of his good friend.