Rheumatoid arthritis is an autoimmune and inflammatory disease that predominantly affects the diarthrodial joints. In this pathology, environmental or behavioral factors can act in synergy with genetic predisposition, accelerating the onset and severity of the disease. This link between the environment and the genome is mediated by epigenetic marks on deoxyribonucleic acid, including its methylation, histone modification, and noncoding ribonucleic acid-mediated regulation. Epigenetics can generate heritable phenotypic changes, which are not determined by modifications in the deoxyribonucleic acid sequence and are therefore reversible. Therefore, diet, medications and other environmental factors would have the ability to modulate them. The identification of a specific epigenetic dysregulation can offer a better understanding of the pathophysiology of the disease and positively influence the prevention, diagnosis and development of new therapeutic targets. Rheumatoid arthritis is an autoimmune and inflammatory disease that predominantly affects the diarthrodial joints. In this pathology, environmental or behavioral factors can act in synergy with genetic predisposition, accelerating the onset and severity of the disease. This link between the environment and the genome is mediated by epigenetic marks on deoxyribonucleic acid, including its methylation, histone modification, and noncoding ribonucleic acid-mediated regulation. Epigenetics can generate heritable phenotypic changes, which are not determined by modifications in the deoxyribonucleic acid sequence and are therefore reversible. Therefore, diet, medications and other environmental factors would have the ability to modulate them. The identification of a specific epigenetic dysregulation can offer a better understanding of the pathophysiology of the disease and positively influence the prevention, diagnosis and development of new therapeutic targets.