Affiliation:
1. Clinical Nutrition and Dietetics Unit Fondazione IRCCS Policlinico San Matteo Pavia Italy
2. Applied Research Division for Cognitive and Psychological Science Istituto Europeo di Oncologia IRCCS Milan Italy
3. Department of Oncology and Hemato‐Oncology University of Milan Milan Italy
4. Department of Oncology Fondazione IRCCS Policlinico San Matteo Pavia Italy
5. Department of Internal Medicine and Medical Therapy University of Pavia Pavia Italy
Abstract
AbstractIntroductionThe most studied anticancer restrictive diets include fasting, fasting‐mimicking diets (FMDs) and ketogenic diets (KDs). Besides the current lack of established clinical benefit and the significant risk of malnutrition and micronutrient deficiencies, dietary restrictions in cancer patients might have relevant psychological effects.Materials and MethodsWe reviewed the randomized and non‐randomized controlled clinical trials (CCTs) reporting data on the psychological impact of fasting, FMDs and KDs in cancer patients. We excluded trials on restrictive diets performed for weight reduction in obese or overweight patients, studies on dietary restrictions lasting less than 24 h, and studies on fasting related to cultural or religious beliefs.ResultsThree CCTs on fasting or FMDs and eight CCTs on KDs in cancer patients were included. In terms of diet‐related distress, emotional, social, and family well‐being, none of these studies showed a detrimental impact of fasting, FMDs and KDs. However, clinical trials specifically assessing the psychological aspects in the long term are lacking.Conclusions and PerspectivesIn the absence of a conclusive evidence on the clinical benefits of restrictive diets, which carry significant risks especially if unsupervised, further studies are needed to clarify their psychological impact in cancer patients. Multidisciplinary approaches including psychological evaluations should be used to ameliorate patient selection for clinical trials, identify early distress symptoms, and increase patient compliance to dietary recommendations.