Aging arises from a complex convergence of inherited influences and lifelong environmental exposures, with epigenetic remodeling positioned at the core of this process. Disruptions in DNA methylation landscapes, altered activity of histone-modifying regulators such as SIRT1 and EZH2, and shifts in non-coding RNA pathways collectively rewire transcriptional programs that govern essential functions, including senescence control and mitochondrial integrity. These changes form a mechanistic “environment–epigenome–pathology” continuum that underlies diverse age-associated conditions, ranging from β-amyloid accumulation in Alzheimer’s disease to atherosclerotic progression, immune aging, bone and muscle degeneration, and cancer development. Because epigenetic marks are fundamentally reversible, the field of epigenetic pharmacology has gained prominence as a strategy to counteract aging biology and related disorders. Manipulating pivotal regulators—such as DNA methyltransferases and histone deacetylases—offers a means to reset maladaptive epigenetic states implicated in disease. This review brings together current knowledge on how epigenetic mechanisms shape aging trajectories, their involvement in major age-linked diseases, and recent progress in developing epigenetic-based therapeutics from foundational studies through clinical advancement. It also evaluates key translational barriers, including precision of target engagement, durability of treatment, and delivery to specific tissues, with the goal of supporting future approaches for diagnosing and treating age-associated disorders.
