Background Food restrictions during periods of neutropenia have been widely used in oncology settings to prevent infections. As there is a lack of clearly demonstrated effectiveness, this strategy is being increasingly questioned. Methods A multi-national panel of 23 individuals was convened to develop a clinical practice guideline (CPG) on the use of food restrictions to prevent infections in paediatric patients with cancer and haematopoietic cell transplantation (HCT) recipients. It included representation from persons with lived experience and physicians, dieticians, nurses, pharmacists and guideline methodologists working in paediatric oncology/HCT or infectious diseases. Panel members (female n = 15; 65%) were from North America (12, 52%), Europe (8, 35%), South America (2, 9%) and Australia (1, 4%). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to formulate the CPG recommendations based on a systematic review of randomised controlled trials (RCTs). MEDLINE, MEDLINE in-Process and Embase databases were searched from January 1, 1980, to May 7, 2024, with a broad strategy which combined subject headings and text words relating to neutropenia, infection and diet. Findings The systematic review, which provided the evidence base for the CPG recommendations, identified 4312 unique citations, of which 52 were retrieved for full-text evaluation. Eight RCTs met the eligibility criteria and informed panel deliberations. Although there was clinical heterogeneity in the food restrictions evaluated, data were consistent in suggesting that food restrictions lack clinically significant benefit in preventing infections. The panel made two conditional recommendations against the use of food restrictions in a) paediatric patients with cancer receiving chemotherapy and b) in the setting of allogeneic and autologous HCT. The panel developed a good practice statement to emphasise the importance of health care organisations and families adhering to local food safety practices. Interpretation This CPG provides the first evidence-based recommendations on use of food restrictions to prevent infections in children and adolescents undergoing chemotherapy and paediatric haematopoietic cell transplant recipients. Copyright (c) 2025 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).