Nonlinear Associations Between Cumulative Dietary Risk Factors and Cardiovascular Diseases, Cancer, and All-Cause Mortality: A Prospective Cohort Study From UK Biobank

Objective To develop a score from cumulative dietary risk factors and examine its nonlinear associations with cardiovascular disease (CVD) and cancer incidence and mortality, as well as all-cause mortality. Patients and Methods There were 422,702 participants from UK Biobank included in this prospective study. Cumulative dietary risk factors were represented using a score ranging from 0 (healthiest) to 9 (least healthy). This was derived from 9 food items based on current UK guidelines using baseline data. Associations between the cumulative score and health outcomes were investigated using nonlinear penalized cubic splines fitted in Cox proportional hazard models. Follow-up was conducted until June 2020 for mortality, and for incidence, up to June 2020 in England and March 2017 in Wales and Scotland. Results The median follow-up period was 9.0 years for incidence outcomes and 9.3 years for mortality outcomes. Each 1-point increment in the cumulative dietary risk factors score was associated with higher risk for incidence and mortality of the outcomes studied. The highest risks were identified for mortality due to heart failure (8.0% higher), CVD, and ischemic heart disease (both 7.0% higher). In addition, a higher diet score accounted for 18.8% of all deaths, 4.47% of incident cases of CVD, 25.5% of CVD deaths, 7.7% of incident cancers, and 18.2% of all cancer deaths. Conclusion Our findings show that dietary risk factors contributed to a large proportion of CVD and cancer events, as well as deaths, among those who did not meet most dietary recommendations.