Do people change their eating habits after a diagnosis of cancer? A systematic review

INTRODUCTION

People who live with and beyond cancer are thought 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.

METHODS

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.

RESULTS

We identified 14 studies with 16,443 participants diagnosed with cancer, 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% CI -0.46 to -0.17) and carbohydrate consumption (SMD 0.20, 95% CI -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.

CONCLUSION

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. This article is protected by copyright. All rights reserved.

Conceptual framework for living with and beyond cancer: A systematic review and narrative synthesis

OBJECTIVE

The concept of living with and beyond cancer is now emerging in policy and literature. Rather than viewing this notion simply as a linear timeline, developing an agreed understanding of the lived experience of people affected by cancer will aid the development of person-centred models of care.

METHODS

A systematic review was conducted. The review question was "What does the term 'living with and beyond cancer' mean to people affected by cancer?" The protocol for the review was preregistered in the PROSPERO database (PROSPERO CRD42017059860). All included studies were qualitative, so narrative synthesis was used to integrate descriptions and definitions of living with and beyond cancer into an empirically based conceptual framework.

RESULTS

Out of 2345 papers that were identified and 180 that were reviewed, a total of 73 papers were included. The synthesis yielded three interlinked themes: Adversity (realising cancer), Restoration (readjusting life with cancer), and Compatibility (reconciling cancer), resulting in the ARC framework.

CONCLUSIONS

Three themes describe the experience of living with and beyond cancer: adversity, restoration, and compatibility. The ARC framework provides an empirically informed grounding for future research and practice in supportive cancer care for this population.