Herbert M. Shelton was an American author, educator, and one of the leading advocates of the Natural Hygiene movement. For more than five decades, he studied and supervised fasting, nutrition, and natural approaches to health, working with people of different ages and conditions. Shelton wrote more than thirty books exploring fasting, healthy living, physiological rest, and the body’s natural capacity for self-repair. His work emphasized the idea that healing is fundamentally a biological process performed by the body itself, while fasting and rest may provide conditions that allow these natural processes to operate more effectively.