Restrictive Diets in Digestive Cancers: Prevalence, Contributing Factors, Foods Concerned and Patients' Beliefs (Prospective Study of 100 Cases)

Cancer is a major cause of disease-related malnutrition; the prevalence of malnutrition and muscle loss is high in digestive cancers and is thought to be associated with a poor prognosis. The aim of this prospective study is to investigate changes in dietary habits following a diagnosis of gastrointestinal cancer that are likely to cause or aggravate malnutrition, to assess the existence of restrictive diets involving the permanent elimination of certain essential aliments (meat, dairy products, etc.), to identify the factors that influence patients to adopt them, and to assess the degree to which patients believe in the effectiveness of these diets in curing cancer.  Materials and Methods: 100 patients aged 18 and over, diagnosed with one of the following digestive cancers: colorectal, gastric, pancreatic, oesophageal, hepatocellular carcinoma or biliary tract cancer; were interviewed using an electronic questionnaire.  Results: Among the patients we interviewed, 69% had adopted a restrictive diet following the diagnosis of digestive cancer. The products permanently eliminated included white sugar and/or sweetened foods in 83% of cases, red meat in 80%, tinned food in 77%, dairy products in 61%, spices in 54%, fried food in 49%, white meat and eggs not produced organically in 44%, processed meat in 33%, and all white meat and eggs in 17% and 14% respectively; This diet was recommended mainly by the patient’s entourage (friends and family) in 81% of cases, by other patients and their relatives (58%) and by personal research on the internet in 36% of cases. In addition, 37% of patients believe that this type of diet contributes to curing cancer.  Conclusion: 69% of patients in the study were on a restrictive diet, and more than a third of them believed that this diet could help cure their digestive cancers. Raising awareness among patients and their families is essential to prevent malnutrition and muscle loss, and thus improve the outcome of the cancer.