Sunlight is one of our most essential needs and cannot be replaced by anything. It provides beauty and health, muscle strength and endurance, as well as energy, joy of life, and mental freshness. Sunlight significantly contributes to the prevention of numerous diseases, and many seemingly incurable patients can regain their health with the help of the sun, as described in this book. On the other hand, a lack of sunlight and improper lighting undermine health. The claim that sunlight causes skin cancer has been debunked – a myth propagated by the anti-sun lobby to profit from fear. This nonfiction book is based on extensive research of the scientific literature and summarizes the impressive, often still unknown knowledge about the health-promoting effects of sunlight.