Cancers attributable to diet in Italy

Cancer burden can be reduced by controlling modifiable risk factors, including diet. We provided an evidence-based assessment of cancer cases and deaths attributable to diet in Italy in 2020. We considered dietary factor-cancer type pairs for which the World Cancer Research Fund/American Institute for Cancer Research – Continuous Update Project reported either ‘convincing’ or ‘probable’ evidence of causal association. Relative risks were retrieved from recent meta-analyses and dietary intakes (around 2005) from a national food consumption survey. Sex-specific population attributable fractions (PAFs) were computed by comparing the distribution of dietary intakes in the Italian population against counterfactual scenarios based on dietary recommendations. Using data from national cancer and mortality registries in 2020, we estimated the number of attributable cancer cases and deaths, assuming ~15-year lag period. Unhealthy diet accounted for 6.3% (95% CI: 2.5%–9.9%) of all cancer cases in men and 4.5% (95% CI: 1.7%–7.4%) in women. PAFs of colorectal cancer were 10.5% and 7.0% for any intake of processed meat, 3.3% and 2.0% for high red meat, 4.8% and 4.3% for low dairy products, and 7.9% and 9.0% for low fiber intakes in men and women, respectively. PAFs for low intake of non-starchy vegetables and fruit ranged from 0.8% to 16.5% in men and 0.6%–17.8% in women for cancers of the aerodigestive tract. The estimated cancer burden associated with unfavorable dietary habits in Italy is considerable, but appears lower than for other high-income countries, reflecting the typically Mediterranean diet.