Postdiagnosis dietary and lifestyle factors and mortality outcomes among colorectal cancer patients: a meta-analysis

Abstract

Background Dietary and lifestyle factors are well-studied for colorectal cancer (CRC) prevention. However, less evidence exists on their impact on CRC survival.Methods PubMed and Embase were searched from inception to September 2024. Summary relative risks (RRs) and 95% confidence intervals (CIs) were estimated using the DerSimonian-Laird random effects model.Results Lower all-cause mortality was observed with unprocessed red meat (summary RR = 0.74, 95% CI = 0.57 to 0.94), whole grains (summary RR = 0.77, 95% CI = 0.66 to 0.90), coffee (summary RR = 0.65, 95% CI = 0.55 to 0.77), milk (summary RR = 0.82, 95% CI = 0.71 to 0.93), low-fat dairy (summary RR = 0.77, 95% CI = 0.64 to 0.94), total calcium (summary RR = 0.76, 95% CI = 0.61 to 0.94), alcohol intake under 45 g/day (J-shaped association), and physical activity (summary RR = 0.55, 95% CI = 0.44 to 0.69). Higher all-cause mortality was observed with refined grains (summary RR = 1.55, 95% CI = 1.03 to 2.33), high-fat dairy (summary RR = 1.34, 95% CI = 1.05 to 1.71), smoking (current: summary RR = 1.49, 95% CI = 1.24 to 1.78; former: summary RR = 1.18, 95% CI = 1.04 to 1.34), and television watching (summary RR = 1.28, 95% CI = 1.06 to 1.55). Risk increased linearly with body mass index greater than 27 kg/m2 but also increased toward lower body mass index. For CRC-specific mortality, most of the results were largely consistent, with calcium supplement showing an inverse association (summary RR = 0.66, 95% CI = 0.47 to 0.94).Conclusions Factors related to CRC survival share differences as well as similarities with established factors related to CRC prevention. To optimize CRC survival, CRC patients may be recommended to adopt a diet rich in whole grains, coffee, milk, and dietary calcium; to avoid excessive alcohol, refined grains, high-fat dairy, sugar-sweetened beverages, smoking, and sedentary lifestyle; and to engage in regular physical activity while maintaining a healthy weight.