Aldossari Amal, Sremanakova Jana, Sowerbutts Anne Marie, Jones Debra, Hann Mark, Burden Sorrel T
Manchester Academic Health Science Centre, School of Health Sciences, University of Manchester, Manchester, UK.
Division of Population Health, Health Services Research & Primary Care, University of Manchester, Manchester, UK.
J Hum Nutr Diet. 2023 Apr;36(2):566-579. doi: 10.1111/jhn.13001. Epub 2022 Apr 12.
People who live with and beyond cancer are considered to be motivated to change their diet. However, there is a lack of reviews conducted on what specific dietary changes people make and further evaluation may inform future interventional studies. Hence, we aim to summarise the evidence on dietary changes in observational studies before and after a cancer diagnosis.
This systematic review followed the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis. Electronic searches were conducted in four databases to identify cohort and cross-sectional studies on dietary changes before and after a cancer diagnosis, excluding studies that evaluated an intervention. Quality assessment was undertaken, and meta-analyses were conducted where suitable.
We identified 14 studies with 16,443 participants diagnosed with cancer, with age range 18-75 years. Dietary change was assessed <1-5 years before diagnosis and up to 12 years post-diagnosis. Meta-analyses showed that the standard mean difference (SMD) for energy (SMD-0.32, 95% confidence interval = -0.46 to -0.17) and carbohydrate consumption (SMD 0.20, 95% confidence interval = -0.27 to -0.14). Studies showed inconsistent findings for fat, protein and fibre, most food groups, and supplement intake. A small decrease in red and processed meat consumption was consistently reported.
All studies reported some positive changes in dietary intake and supplement consumption after receiving a cancer diagnosis without any intervention. However, differences for food groups and nutrients were mainly small and not necessarily clinically meaningful. Evidence demonstrates that a cancer diagnosis alone is insufficient to motivate people to change their dietary intake, indicating that most people would benefit from a dietary intervention to facilitate change.
癌症患者及康复者被认为有改变饮食的动机。然而，对于人们具体做出了哪些饮食改变，缺乏相关综述，进一步的评估可能为未来的干预研究提供信息。因此，我们旨在总结观察性研究中癌症诊断前后饮食变化的证据。
本系统综述遵循系统评价与Meta分析的首选报告项目指南。在四个数据库中进行电子检索，以识别关于癌症诊断前后饮食变化的队列研究和横断面研究，排除评估干预措施的研究。进行质量评估，并在合适的情况下进行Meta分析。
我们纳入了14项研究，共16443名年龄在18至75岁之间的癌症确诊患者。饮食变化在诊断前<1至5年以及诊断后长达12年进行评估。Meta分析显示，能量摄入的标准平均差（SMD）为-0.32，95%置信区间为-0.46至-0.17，碳水化合物摄入量的SMD为0.20，95%置信区间为-0.27至-0.14。关于脂肪、蛋白质、纤维、大多数食物组和补充剂摄入的研究结果不一致。一致报告红肉和加工肉的消费量略有下降。
所有研究均报告，在未经任何干预的情况下，癌症确诊后饮食摄入量和补充剂消费量有一些积极变化。然而，不同食物组和营养素的差异主要较小，不一定具有临床意义。证据表明，仅癌症诊断不足以促使人们改变饮食摄入量，这表明大多数人将受益于促进改变的饮食干预。
