Meat intake and cancer risk: prospective analyses in UK Biobank
Knuppel A., Papier K., Fensom G., Appleby P., Schmidt J., Tong T., Travis R., Key T., Perez-Cornago A.
Background: Red and processed meat has been consistently associated with risk for colorectal cancer, but evidence for other cancer sites is limited and few studies have examined the association between poultry intake and cancer risk. We examined associations between total meat, red meat, processed meat and poultry intake and incidence for 20 common cancer sites. Methods and Findings: We analysed data from 475,023 participants (54% women) in UK Biobank. Participants were aged 37 73 years and cancer free at baseline. Information on meat consumption was based on a touchscreen questionnaire completed at baseline covering type and frequency of meat intake. Diet intake was re-measured a minimum of three times in a subsample (15%) using a web-based 24h dietary recall questionnaire. Multivariable-adjusted Cox proportional hazards models were used to determine the association between baseline meat intake and cancer incidence. Trends in risk across baseline meat intake categories were calculated by assigning a mean value to each category using estimates from the re-measured meat intakes. During a mean follow-up of 6.9 years, 28,955 participants were diagnosed with a malignant cancer. Total, red and processed meat intakes were each positively associated with risk of colorectal cancer (e.g. hazard ratio (HR) per 70 g/day higher intake of red and processed meat combined 1.31, 95%-confidence interval (CI) 1.14-1.52). Red meat intake was positively associated with breast cancer (HR per 50 g/day higher intake 1.12, 1.01-1.24) and prostate cancer (1.15, 1.03-1.29). Poultry intake was positively associated with risk for cancers of the lymphatic and hematopoietic tissues (HR per 30g/day higher intake 1.16, 1.03-1.32). Only the associations with colorectal cancer were robust to Bonferroni correction for multiple comparisons. Study limitations include unrepresentativeness of the study sample for the UK population, low case numbers for less common cancers and the possibility of residual confounding. Conclusions: Higher intakes of red and processed meat were associated with a higher risk of colorectal cancer. The observed positive associations of red meat consumption with breast and prostate cancer, and poultry intake with cancers of the lymphatic and hematopoietic tissues, require further investigation.