The Science of Sun Exposure

For decades, we have been told to fear the sun — slather on sunscreen, avoid midday rays, cover every inch of skin. Yet sunlight is essential to human health. It triggers vitamin D synthesis, regulates our internal clock, boosts mood, and even helps lower blood pressure. So how do we find the sweet spot between deficiency and overexposure? In The Science of Sun Exposure, science writer Elena Marsh Whitfield cuts through the noise to offer a clear, evidence-informed guide. You will learn how ultraviolet and visible light affect your body, why your personal safe dose depends on skin type, latitude, and season, and how to protect yourself without sacrificing the benefits. The book covers sensible sun practices, the latest consensus on sunscreen, and practical routines for children, adults, and older adults. Each chapter is grounded in mainstream medical consensus — not hype or anecdote. Whether you live in cloudy Seattle or sunny Phoenix, this book will help you make confident, daily sun decisions. Part of The Sagewell Wellness Library.