The woman sitting across from Kathy Miller, MD, had arrived too late. Not late for her appointment — late for the kind of treatment that might have saved her life.

Months earlier, when her cancer was still confined, still beatable, she had chosen high dose vitamin C along with ivermectin and mebendazole — two drugs commonly used to treat parasites — after discovering tips from people on social media who promised that Big Pharma was hiding the real cures.

Miller, a breast oncologist at Indiana University Health, Indianapolis, now faced the delicate task of explaining how far the disease had progressed without saying what hung in the air between them: You could have been cured.

“I don’t have any way that I could tell those people, if you had come to me initially, you wouldn’t be in this situation,” Miller said. “That would be unfair to them because the treatments I have don’t cure everybody.”

This dance between evidence and hope has become a defining feature of modern oncology. Across the US, oncologists are discovering that one of their greatest challenges isn’t just fighting tumors but navigating a lucrative global wellness universe that has captured the imagination of many patients. The wellness industry spans thousands of social media influencers, touting advice on everything — diet, supplements, alternative drugs, fitness, even stem cell injections. The advice has permeated the oncology arena, and much of it is inaccurate, even harmful.

While it’s hard to pin down the scope of influencer-fueled cancer misinformation and how many patients follow it, the allure of this advice can be strong — it can provide the hope and definitive answers patients crave and can appeal to a growing mistrust of experts with formal training.

As a result, oncologists often find themselves walking a delicate line between highlighting the real dangers of taking treatment advice from influencers and addressing patients’ real concerns about their cancer and care.

The stakes are high for oncologists and patients navigating this space: The patients who embrace an alternative approach and forgo evidence-based treatments “will die sooner,” said Laure-Anne Teuwen, MD, PhD, a medical oncologist at Antwerp University Hospital, Antwerp, Belgium. “That has been studied.”

Inside Dr Influencer

Scroll through any cancer support group or peruse wellness influencers’ social media accounts, and you’ll find warnings against conventional cancer care and testimonials about alternatives. Videos or posts can garner hundreds of thousands of views, and thousands of comments from people highlighting “miracle” cures and suspicions about conventional medicine.

In recent years, researchers have attempted to capture the scale of this cancer misinformation on social media. A survey, published in 2023, revealed that more than half of US adults saw cancer misinformation on social media, and that rate was much higher — nearly 71% — among patients with cancer and caregivers.

A 2021 study, which assessed 200 of the most popular social media articles on Facebook and other sites, found that about one third contained misinformation and more than 30% contained harmful information. A more recent analysis reported even higher rates of cancer misinformation online, revealing that 81% of cancer cures promoted on TikTok were not evidence-based.

The current stars of these social media claims in oncology are ivermectin, mebendazole, and fenbendazole. All three are used to treat parasitic infections; fenbendazole is used in veterinary medicine and not approved for human use.

“We humans typically establish our own dogmas, and that’s happening with those medications,” said Arturo Loaiza-Bonilla, MD, chief of Hematology and Oncology at St. Luke’s University Health Network in Allentown, Pennsylvania.

Each physician Medscape Medical News spoke to said that many of their patients ask whether ivermectin can treat their cancer, a trend that began during the pandemic.

A few studies have shown that ivermectin can have anti-tumor properties in a petri dish. While many substances can kill cancer cells in the lab, few prove to help humans. However, on social media, the existence of this early-stage data can become proof of a conspiracy.

Claims about the cancer benefits of extreme diets or herbal and dietary supplements are also common. Turmeric, which contains the antioxidant curcumin, is particularly popular for its potential anticancer activity, with some studies suggesting the spice has anticancer properties.

But “you have to basically consume so much turmeric to even see any hope of having your blood levels reflect that kind of anticarcinogenic effect,” explained Don Dizon, MD, chief of Hematology and oncology at Tufts Medical Center, Boston. “It’s just not humanly possible.”

Some people are also turning to extreme diets, like long-term water-only fasts. While mouse studies suggest fasting might have benefits, these approaches haven’t been proven safe or effective in human clinical trials.

The harms of embracing alternative options over standards of care are real.

A 2018 analysis found that, among patients with curable cancers, use of alternative medicine instead of conventional cancer therapies was independently associated with 2.5-fold greater risk for dying. Among those with breast and colorectal cancers, the risk for dying was even higher — 5.7-fold for breast cancer and about 4.5-fold for colorectal cancer.

Another study revealed that patients with cancer who chose complementary medicine were more likely to refuse additional conventional treatment and had worse 5-year overall survival than those who did not receive complementary care. The findings suggest that the elevated risk for death tied to complementary medicine was “linked to its association with treatment refusal,” the researchers said.

While social media can have some benefits, such as raising awareness or spurring patients to initiate healthy lifestyle changes, “social media can also have significant downsides for patients with cancer,” including promotion of unproven or dangerous treatments, said Stacy Loeb, MD, a urologist and public health professor at New York University who studies the impacts of social media on cancer care.

The Architecture of Mistrust

Perry Halkitis, PhD, MPH, a professor of biostatistics and epidemiology at Rutgers, has spent years studying why a person with a potentially curable cancer would choose herbs, supplements, or an untested drug over approved cancer treatments.

It often comes down to a lack of trust.

These aren’t irrational people, Halkitis said. Their “mistrust grows from lived experiences, emotional realities, or social conditions.” 

The wellness industry has also mastered something that traditional medicine often fumbles — it makes people feel seen, Halkitis explained. While knowledge matters, emotions are probably a stronger force in shaping behavior, he said.

Another big part of what makes alternative medicine so seductive is that it can offer absolute answers, whereas conventional oncology is built on a foundation of probability and uncertainty. Even the most promising cancer treatments come with caveats, percentages, and ranges of possible outcomes. However, wellness influencers can appeal to people’s desire for certainty and hope by offering compelling testimonials or transformation stories and hiding cases that don’t go well.

“Folks like me can never definitively say that things don’t work,” said Dizon. There are logical reasons why an alternative option won’t help, or could even be dangerous, but randomized trials don’t necessarily show that, he explained.

Sometimes this uncertainty calcifies into something darker. Miller recalled a particularly brutal encounter: A patient’s husband accused Miller of hiding the cure for cancer, of being part of a conspiracy driven by profit.

“I had just come from sending a 31-year-old woman with two children home on hospice care,” she recalled. “Do you have any idea how insulting that is? Having just done that, to be told I could have saved her, I just chose not to?”

The Integrative Path

Not everything outside conventional medicine is snake oil. But legitimate complementary or integrative therapies — approaches that could genuinely help patients alongside conventional care — sometimes get lumped together with alternative options.

Teuwen explained the difference: Integrative medicine combines conventional treatment with evidence-based complementary approaches, while alternative medicine means rejecting conventional care.

There is good evidence to support integrating complementary approaches into evidence-based treatment, especially to help patients manage symptoms, said Alissa Huston, MD, an oncologist at the Wilmot Cancer Institute, University of Rochester, Rochester, New York.

Research indicates, for instance, that ginseng may have some efficacy in reducing cancer-related fatigue; meditation, art therapy, or yoga can improve depression and anxiety in patients; and acupuncture can reduce chemotherapy-induced nausea and vomiting or help alleviate pain.

“What we’re trying to show is that you can have a space where patients can receive standard of care cancer treatment, but we can also pull in integrative modalities to really help support our patients in a whole person approach,” said Huston.

However, while a handful of cancer institutions across the US integrate complementary approaches into routine care, most don’t. Complementary medicine often relies on funding from donations — it generally cannot sustain itself through patient payments alone, noted Huston.

While complementary approaches can improve symptoms and quality of life, the impacts on survival outcomes are not so clear cut.

The best data we have, Miller noted, is that people who eat a well-balanced diet, exercise regularly, and have a healthy body weight are less likely to develop cancer, and if they do, they often have a better outcome.

Exercise programs likely show the most promise for improving cancer outcomes. Teuwen pointed to the best evidence to date, which found that patients with colon cancer who participated in a structured exercise program lived longer than those who only received health education.

Dietary interventions generally show more limited effects on outcomes. A 2024 review examined multiple studies on cancer and diet “and none of them actually had an effect on survival,” Teuwen said.

But more studies on diet and cancer are underway.

For instance, Jethro Hu, MD, a neurosurgeon at Torrance Memorial Medical Center in California, is running a phase 2 randomized clinical trial on ketogenic diets for glioblastoma, after phase 1 data showed promising survival outcomes among patients receiving a keto diet plus standard chemoradiation. Although the small phase 1 study was focused on safety and feasibility, Hu is hopeful that the phase 2 data will be powered to show more definitively whether the keto diet improves outcomes for patients.

Bridging the Divide

An unfortunate outcome in this clash between conventional and alternative medicine isn’t just that patients may choose ineffective treatments. It’s that polarization can prevent us from addressing what the wellness industry gets right — the need to treat patients as complete human beings, not just collections of rebellious cells.

“I have a psychological life, an emotional life, a familial life, and a religious life, and you’re not addressing any of those things in medical care,” Halkitis observed. “The medical profession stinks at this.”

Dizon has evolved his own honest and collaborative approach through years of practice. “We’re here to provide advice. We don’t have the right answers,” he said.

This admission of fallibility can strengthen the doctor-patient relationship.

“Where people bristle is when they’re told, you have to do this and there’s no other way to do it. Then they start looking for other ways,” Dizon said.

The path forward, according to Halkitis, requires fundamental changes in how physicians communicate.

“Acknowledge people’s fears, don’t dismiss them,” he said. “Be empathetic, validate emotions, respect experiences, and pair evidence with humanity. When patients feel seen and heard, they’re more likely to trust and they’re more likely to follow treatment.”

This extends to how doctors handle patients’ questions. Fear of criticism can drive patients to pursue other options in secret. That can mean patients turn to supplements without informing their oncologist, and some supplements can interact with cancer therapies, making them less effective.

The challenge for modern medicine is to maintain scientific standards while attending to patients’ emotional and spiritual needs.

Considering the patient as more than their disease is where complementary therapies do “extremely well,” Halkitis said, “I’m not just a patient, not just a biological entity that has cancer in me.”

Perhaps nowhere is this balance more delicate than when patients who initially chose alternative treatments return with advanced disease. Miller has developed a careful response for these moments, telling patients, “I’m very sorry that it didn’t work the way you needed it to, and I’m glad you’re here now.”