DASH, plant-based diets help prevent gastrointestinal cancers

People who follow a healthy eating pattern, such as the dietary approach to stop hypertension (DASH) or the healthful plant-based diet index (hPDI), have a lower risk of gastrointestinal cancers (GIC), suggests a study. These dietary patterns also appear to partly compensate for genetic predispositions to cancer.

A total of 105,463 participants in the UK Biobank aged 40‒72 years and who were cancer-free at baseline were included in this prospective cohort study. Dietary pattern scores, including DASH and hPDI, were calculated using dietary intake (Oxford WebQ).

The investigators quantified genetic risk using a polygenic risk score (PRS) consisting of 129 known GIC-related loci. They also estimated the relationships of dietary patterns and PRS with GIC incidence using Cox proportional hazards regression, with adjustments for potential confounders.

GIC was diagnosed in 1,661 participants over a median follow-up of 11.70 years. DASH and hPDI both correlated with a decrease in GIC risk (20-percent and 36-percent reductions, respectively). Low PRS was also associated with a 30-percent decrease in GIC risk (hazard ratio [HR], 0.70, 95 percent confidence interval [CI], 0.62‒0.79).

Notably, individuals at high genetic risk with healthy dietary scores had a lower GIC risk (DASH: HR, 0.77, 95 percent CI, 0.60‒0.98; hPDI: HR, 0.66, 95 percent CI, 0.52‒0.84) than those with unhealthy dietary score. Participants with both high dietary score and low genetic risk had the lowest GIC risk (DASH: HR, 0.58, 95 percent CI, 0.45‒0.75; hPDI: HR, 0.45, 95 percent CI, 0.34‒0.58).

“Our results advance the development of precision medicine strategies that consider both dietary patterns and genetics to improve gastrointestinal health,” the investigators said.