DASH Diet, Dietary Nitrate, and Nitric Oxide Bioavailability: Implications for Endothelial Dysfunction and Hypertension in Older Adults.
Hypertension in the elderly is closely associated with vascular aging, characterized by endothelial dysfunction (ED) and a progressive decline in nitric oxide (NO) bioavailability. Age-related dysfunction of endothelial nitric oxide synthase (eNOS), compounded by increased oxidative stress, creates a vicious cycle of oxidative-nitrosative imbalance, leading to chronic inflammation and arterial stiffness. The Dietary Approaches to Stop Hypertension (DASH) diet was developed as a primary intervention to restore NO balance by protecting endogenous pathways and supplying alternative nitrate-nitrite-NO precursors. However, its cardiovascular benefits are often diminished by age-related alterations in nitrate metabolism and the extensive use of multiple medications in the elderly. Thus, while restoring balance remains a key therapeutic goal, future clinical strategies must evolve from broad dietary recommendations to more personalized, precise nutritional approaches, considering the unique physiological and pharmacological challenges faced by older adults.