Abstract
Early life environment predicts future health. The initial precedents and research focus on this concept arose out of historical events. However, this concept continues to be relevant as evidenced by the recent Chinese famine and the evidence of racial disparities in the United States. The latter allows us to introduce the "life course model" and "weathering" as relevant epigenetic phenomena. We then review the molecular components of environmental epigenetics. We subsequently present glucocorticoid receptor biology as a paradigm that involves all of the components. Finally, we suggest that environmental epigenetics are a key component of the future of personalized medicine.