This book is about the health promoting hormone DHEA, how it is affected by psychological stress, and how we can positively affect our levels of it. It starts explaining stress and how that can cause bad health. It then describes the physiology, functions and protective mechanisms down to the cell level of the hormone DHEA and its metabolite DHEA-S. Research studies including the most recent ones on the effects of acute and long-term stress on DHEA and DHEA-S are reviewed. Then, the text looks into the possibility to restore and reverse reduced DHEA and DHEA-S levels. The book is suitable for medical doctors, researchers and people who want to understand the science behind this health promoting hormone which is often labeled a "Youth Hormone".