Trends in dietary patterns over the last decade and their association with long-term mortality in general US populations with undiagnosed and diagnosed diabetes

Background: Dietary management is important in diabetes care, yet trends in dietary patterns among US adults with diagnosed and undiagnosed diabetes over the past decade and their links to long-term outcomes are unclear. This study estimated dietary patterns by baseline diabetes status and examined associations with long-term mortality. Methods: Using NHANES 2007–2018, adults were categorized as without diabetes, undiagnosed diabetes, or diagnosed diabetes. Dietary patterns were assessed with the Healthy Eating Index (HEI) and Dietary Inflammatory Index (DII). Weighted survival analyses related HEI/DII to all-cause and cause-specific mortality. Results: Diabetes prevalence increased over the last decade. HEI scores declined in all three groups in recent years. Undiagnosed diabetes had lower HEI (weighted mean 50.85, 95% CI 49.79–51.36) than diagnosed diabetes (51.59, 95% CI 50.93–52.25). Both undiagnosed and diagnosed diabetes groups had higher DII scores than those without diabetes, indicating greater dietary inflammatory potential. Higher HEI was associated with lower all-cause and cause-specific mortality, and higher DII with higher mortality. Conclusions: With rising diabetes prevalence, dietary management is increasingly crucial; dietary intervention should be considered an essential component of diabetes care.