A series of laboratory and field experiments demonstrated that stress, long thought to be an exclusively psychological phenomenon, is measurable and dangerous on a physical level. Stanford neurobiologist Dr. Robert Sapolsky studied baboons (Papio) on the Masai Mara Reserve in Kenya, measuring their levels of stress hormones caused by social hierarchies. Sapolsky found that the hormones adrenaline and glucocorticoid increase in subordinate troop members, and dominant males had significantly lower blood pressure and heart rates. Also working with nonhuman primate models, Dr. Carol Shively of Wake Forest University examined the arteries of rhesus macaques (Macaca mulatta). Corroborating Sapolsky's findings, Shively demonstrated that subordinate macaques have higher plaque levels in arteries, potentially increasing the risk for heart attack. These results were compared to a long-term human study, directed by Sir Michael Marmot of the University of London Medical School. Tracking the health of British Civil Servants, Marmot found that that humans lower in the workplace hierarchy had higher stress levels, and higher rates of sickness. Several researchers took these results a step further, focusing in on how stress affects mothers. Dr. Elizabeth Blackburn and Dr. Elissa Epel of the University of California-San Francisco found that chronic high stress in mothers shortened telomeres in chromosomes, potentially producing lifelong consequences. In all of these studies, researchers found that stress and its harmful effects can be reduced by social interaction, and that grooming, playing, and equal social rank in nonhuman primates produced positive health effects.

Contents: A Hunch -- Survival -- Control -- Rank -- Ulcers -- Dangerous fat -- Scars of war -- Ageing -- A Remedy .