This book is dedicated to the late Dr. Leo Roy, my friend and mentor, who first brought my attention to the significance of the subtle functioning of the endocrine glands and how important they are in health and illness. Leo showed me the power of natural therapies and the importance of nutrition in health and disease. Many times I watched him take people on their last legs and rehabilitate them to full health, primarily using food concentrates and glandular extracts. He was a uniquely gifted physician whose absence is sorely felt.