Unqualified “Wellness Guru” Leaves Cancer Patient Malnourished After Unfounded Dietary Advice

A 63-year-old cancer patient lost more than three stone in weight and became severely malnourished after following dietary advice from an unqualified “wellbeing expert” recommended through his private health insurance provider.

The man, who had undergone surgery to remove a neuroendocrine tumour from his small intestine in 2024, was struggling with frequent and urgent bowel movements post-discharge when he sought nutritional guidance through a wellbeing service advertised by his insurer.

The disturbing case was presented at a recent seminar in Dublin titled “Decoding Nutrition Information: Separating Fact from Fiction,” hosted by SafeFood, a government-funded all-Ireland organisation.

Surgical dietitian Úna Donnelly from St. Vincent’s Private Hospital detailed the alarming consequences of the inappropriate advice. When the patient returned to hospital for a second surgery due to tumour recurrence just 11 months later, he had lost 20 kilos – 22 percent of his body weight.

“He was quite malnourished then, obviously, coming into hospital, heading into a second surgery, heading into another oncology diagnosis,” Donnelly explained.

The cause became clear after investigation. The wellbeing provider had recommended eliminating numerous foods based on an IgG blood test, which purportedly identifies food allergies through antibody responses. However, Donnelly emphasized, “There’s currently no evidence to support IgG blood tests. It’s not recommended as a diagnostic tool and it is not recommended to introduce any dietary restrictions based on the results.”

Despite this lack of scientific backing, the patient was advised to stop consuming gluten, dairy, potatoes, caffeine, cashew nuts, beer and wine. Instead, he was directed to consume bone broth, probiotics, sea salt, glutamine powder and manuka honey – none of which would address his medical condition.

“This individual was quite confident to give him dietary advice, even though these are really not symptoms that can be managed with diet. It has to be managed with medication,” Donnelly noted. The ill-informed guidance not only failed to improve the patient’s bowel problems but also worsened his social isolation and created fear around eating the very foods he needed for recovery.

The case highlights a growing problem in nutrition advice. While “dietitian” is a protected professional term in Ireland requiring Coru registration (the regulatory body for health and social-care professionals), anyone can call themselves a “nutritionist” with minimal or no qualifications. This regulatory gap has long frustrated degree-qualified, professional nutritionists, and the NutriPD project, based at Atlantic Technological University in Galway, is currently advocating for change.

Social media has dramatically amplified the spread of nutrition misinformation. “This gave a megaphone to everyone and anyone, and gave them the power to be able to spread misinformation rapidly,” said Robbie Locke, founder of the Freedom Food Alliance, at the seminar. Now AI technologies further complicate matters by generating “misinformation on an industrial scale” through chatbots and social media.

The consequences can be severe. Locke referenced a documented case of a 60-year-old American man who consulted ChatGPT about removing table salt from his diet, subsequently began taking bromide salt, developed bromism, and required psychiatric treatment for psychosis.

To address these issues, Locke and Elise Hutchinson created FoodFacts (foodfacts.org) in February to help debunk diet myths and demystify food information. At the seminar, Hutchinson discussed the psychology behind misinformation’s persistence.

“Nutrition-based information rarely begins with a complete lie. What it begins with really is doubt,” she explained. This doubt creates space for alternative narratives questioning established medical knowledge.

The scale of the problem is significant. According to a Dublin City University study published last year, only two percent of TikTok nutrition videos align with established nutritional guidelines. Yet 57 percent of millennial and Gen Z TikTok users reported being influenced by nutrition trends from the platform, with nearly a third experiencing adverse effects from “fad diets.”

Financial incentives drive much of this misinformation. A study of 54 “super spreaders” of nutrition misinformation on Instagram – collectively reaching 24 million followers – found 96 percent had clear financial motivations, according to Marlana Malerich, cofounder of the Rooted Research Collective. “Many sold health packets or coaching; they often sold supplements,” she said. “There were some that we were able to estimate earned up to $100,000 [€86,000] per month across multiple channels.”

For the cancer patient in Donnelly’s care, intervention finally came in the form of proper medical treatment. She started him on pancreatic enzyme replacement therapy along with nutritional supplement drinks, gradually reintroducing foods he had been wrongly told to avoid. Through building trust and explaining the scientific basis for her recommendations, Donnelly helped improve his condition before discharge.

“By the time he was leaving the hospital, we did get his bowels under control. His quality of life was starting to improve. He was going to be able to socialise; to go out of the house,” she said.

Ironically, the extended hospital stay necessitated by his malnourished condition – at €1,500 per night for seven additional nights – was billed to the same private health insurance provider that had connected him with the unqualified “wellbeing expert” in the first place.