Sleep After 40 is a calm, practical guide to the nighttime changes that can make mornings feel less dependable. Jonah Bracken Holt explains how sleep timing, light, caffeine, alcohol, temperature, stress, movement, food, hormonal shifts, and breathing-related problems can shape rest and daytime energy. With a seven-day log, practical experiments, appointment questions, red-flag guidance, and clinician routing, this warm nonfiction companion helps readers test small changes while keeping individual variation and medical care in view. Educational information only; not a substitute for personalized medical advice.