was ist epigenetik — what are common causes?

Epigenetics refers to heritable changes in gene activity that do not alter the DNA sequence. Common causes include diet (e.g., folate deficiency, caloric restriction), chronic stress, smoking, air pollution, sleep deprivation, and physical activity. Aging itself drives epigenetic drift (e.g., DNA methylation clocks). Evidence is human-strong for some factors (smoking, diet) and moderate for others (stress, toxins). Key point: Epigenetics is dynamic and reversible – it explains how lifestyle modulates gene expression, but direct-to-consumer tests claiming to measure 'epigenetic age' or 'risk' often overstate clinical utility. No single marker reliably predicts your biological age or disease risk. The field is promising but not yet ready for individual clinical decisions without medical oversight.