You are what you eat: can your diet cure your cancer?


With so-called superfoods and organic diets being marketed as disease-preventing, Aoife Loughnane asks if changing your diet can save your life?

You only have to type “cancer diets” into Google to be met with a seemingly never-ending list of particular ways of eating or “hacks” and “secrets” that will help you to prevent and/or beat the disease.

The range of alleged cancer-curing diets includes the Ketogenic (replacing carbohydrates with healthy fats and protein) Macrobiotic (basically go vegetarian and then some) and Gerson therapy (coffee enemas anyone?).

The danger of taking up diets that are advocated online can be seen in the scandal of Australian blogger Belle Gibson. Gibson is the author of both the app and cookbook, The Whole Pantry. Her claims that she was suffering form multiple types of cancer and that she had fundraised and donated to charities proved fraudulent in 2015.

Gibson had claimed that she had treated various cancers – brain, kidney, uterus – through an altered diet and Gerson therapy. A book deal and sales of over 1 million dollars ensued before Gibson was discovered to be a fake.


A nutrient-dense, primarily plant-based diet can lower the risk of chronic diseases, diabetes and cancer, and can help us to live longer, more vibrant, energetic lives.”

– Bernadette Bohan, bestselling author and cancer survivor


The Irish Cancer Society warns patients not to fall into this trap of false information. “It is also irresponsible for individuals to communicate inaccurate advice which could prey on the vulnerabilities and needs of patients who are undergoing treatment for cancer by proposing a diet that has no real evidence to support it,” representative Michael Hale says.


The cancer survivors

The opinions of doctors, nutritionists, dietitians, pharmacists and cancer survivors themselves vary greatly in crediting certain ways of eating and living for helping to cure them. Bernadette Bohan is a two-time breast cancer survivor who has written a variety of bestselling books such as Eat Yourself Well and Raw, based on her four-step plan The Choice. After her second diagnosis, Bohan embraced a plant-based diet in the hopes of recovery.

Bohan had the conventional treatment of chemotherapy twice, but the second time around, she decided to also overhaul her eating habits and has been cancer-free ever since.  Bohan swears by her four-step plan in curing her of cancer, so what exactly is it all about?

Bohan: I embraced a plant-based, living food diet and shortly after I saw real results; losing weight and improved eyesight. My programme is based on drinking green juices, eating organic living foods and eliminating the personal care products that are loaded with chemicals. It is based on the principle that a nutrient-dense, primarily plant-based diet can lower the risk of chronic diseases, such as heart disease, diabetes and cancer, and can help us to live longer, more vibrant, energetic lives.

There are so many trends that claim to cure cancer – is there actually a direct link between cancer and a person’s diet?

Bohan: Yes, and my programme makes complete sense as it is eating foods as Mother Nature intended us to. I also strongly believe in the words of Dr Carl Simonton: “If the patient actively participates in their recovery they may well exceed their life expectancy and significantly alter the quality of their life.”

Watch Bohan on The Morning Show speaking about The Survivor’s Mindset

Why do you think medicine avoids issues like diet and nutrition?  

Bohan: This baffles me as good nutrition is so important especially for sick people. If you look at the work of Dr. T. Colin Campbell, nutritional biochemist at Cornell University in the China Study it’s a wonder that his finding are not mandatory for all of us.  His findings showed that people who ate even small amounts of animal proteins had the most chronic disease.

Irish author Emma Hannigan is battling cancer for the tenth time. 12 years ago, she discovered that she was carrying a potentially deadly cancer carrying gene, BrCa 1. Her approach to diet differs from Bohan’s.

“I’ve come to the conclusion that the best thing for me is to have a healthy diet with no processed foods and to have everything in moderation,” Hannigan says. “I don’t believe that avoiding certain foods will cure cancer. I don’t believe that excluding food groups from a diet can cure cancer either. I believe in listening to my own doctor and backing up his treatments with healthy nutritious food and exercise.”


“Cancer patients are encouraged to follow prescribed medical treatments by their oncologists and, in conjunction with this follow a high protein high calorie diet.”

                                                                                                                    – The Irish Cancer Society 


The medical opinion

While people like Bohan maintain that “cancers love sugar -so don’t give them sugar,” over on the medical side of things the attitude towards diet and curing cancer is rather dismissive.

“I think that it’s just people jumping on the healthy eating bandwagon,” pharmacist Fiona Hayden remarks.  “Changing your diet can’t cure cancer but a healthy diet is important to assist your body’s recovery from cancer.”

Michael Hale of the Irish Cancer Society agrees that following certain diets can adversely affect the chances of recovery.  He provided the following statement issued by the Irish Cancer Society, the Irish Society of Medical Oncology and Irish Nutrition and Dietetic Institute on the matter. “Dietary issues pertaining to cancer need care from recognised professional dietitians and clinicians who can give personalised guidance and support.” He continued: “Cancer patients are encouraged to follow prescribed medical treatments by their oncologists and, in conjunction with this follow a high-protein high-calorie diet.”

The information about what food and vitamins are most likely to kill cancer is conflicting. And not only that, but it is also potentially very dangerous. If people are choosing to follow certain diets that they believe will rid them of cancer and this information proves false, then that could ironically deteriorate their chances of recovery.

While a healthy diet is essential for a healthy body and mind, one must be careful in adopting recommended alternative diets. Always consult your doctor or professional dietician before making any significant changes.

Featured image by RichKnowles via Flickr, all creative commons

One comment

  1. Wonderful article. Very interesting. I am currently teaching a nutrition course and will use this article as extra reading. Well done Aoife Loughnane

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