Polyphenols,　abundant　in　tea,　fruits,　vegetables,　and　other　plant-derived　foods,　have　emerged　as　key　bioactive　ingredients　in　the　field　of　nutritional　epigenetics.　These　polyphenols　can　modulate　epigenetic　modifications　through　endogenous　metabolic　pathways　that　are　highly　sensitive　to　food　signals.　Among　these,　the　methionine　cycle　plays　a　central　role　in　maintaining　the　homeostasis　of　DNA,　histone,　and　RNA　methylation　by　controlling　the　cellular　supply　of　S-adenosylmethionine　(SAM),　the　universal　methyl　donor.　Dietary　polyphenols　influence　this　cycle　through　multiple　mechanisms,　including　the　regulation　of　methionine　adenosyltransferase　activity,　modulation　of　SAM　biosynthesis,　and　promotion　of　S-adenosylhomocysteine　clearance.　These　actions　help　restore　methylation　balance　and　contribute　to　the　dietary　prevention　of　metabolic,　inflammatory,　and　age-related　diseases.　Furthermore,　polyphenols　are　biotransformed　in　the　gut　microbiota　to　produce　metabolites　that　further　influence　methionine　metabolism　and　its　associated　epigenetic　modifications.　This　review　provides　an　overview　of　dietary　polyphenols　as　functional　food　supplements　that　play　a　role　in　methionine　metabolic　homeostasis　and　epigenetic　modification.　This　review　provides　new　perspectives　for　the　development　of　precision　nutrition　strategies,　functional　foods,　and　chronic　disease　prevention　approaches.　©　2025　Taylor　&　Francis　Group,　LLC.