Dietary modification for Premature Ventricular Contractions (PVCs) primarily involves reducing intake of stimulants like caffeine and alcohol, which can exacerbate arrhythmias by increasing sympathetic nervous system activity and myocardial excitability. This approach indirectly stabilizes cardiac electrophysiology by minimizing triggers that promote ectopic ventricular beats, thereby reducing PVC frequency and severity without direct pharmacological action.