Epigenetic changes and their potential reversibility in mental health disorders.

Mental health disorder (MHD) incidence rates continue to rise, contributing significantly to the global disease burden. While their aetiology was once thought to be strictly genetic or environmental, the study of epigenetics has reshaped our understanding of their underlying mechanisms. Environmental exposures are understood as key players in the development of MHDs. Growing research has elucidated the critical role of environmental chemical exposures-particularly through endocrine-disrupting chemicals and heavy metals-in influencing MHD incidence through epigenetic mechanisms (i.e. DNA methylation, histone modification and non-coding RNA action). A key breakthrough in this field is the recognition that epigenetic modifications are not necessarily permanent. By exploiting the potential reversibility of DNA methylation and histone modification, new avenues for therapeutic interventions open, in which normal gene function could be restored. Understanding and harnessing epigenetic reversibility not only provides hope for novel and personalized treatment strategies but also underscores the importance of environmental protection policies in mental health prevention.