Time-restricted eating (TRE) is a form of intermittent fasting that limits daily energy intake to a 4–12 hour window without explicit caloric restriction. Proposed mechanisms include enhanced circadian-regulated metabolic gene expression, increased insulin sensitivity during the fasting period, and spontaneous caloric reduction (typically 200–500 kcal/day). RCTs show 1–4% body weight reduction over 8–12 weeks, with improvements in fasting insulin and blood pressure.