It seldom happens when we go through a day without experiencing stress. We are especially familiar with these feelings when they build up after a long day at work or while studying for a difficult final exam. In our modern industrialized world, it is more difficult now than ever to avoid stress, and some experts say this is leading to many unforeseen health-related problems. In a society that values multi-tasking, an over consumption of commercial goods, and exponential increases in economic production, no wonder it always feels like our heads are spinning and no wonder life often seems so hectic and uncontrollable.

However, stress is a necessary component to the human experience. Neurobiologist Robert Sapolsky, who is featured in the PBS documentary “Stress: Portrait Of A Killer,” explains how stress is an adaptive response of our nervous system. According to him, there are two main hormones involved in this stress response: epinephrine (also called “adrenaline”) and norepinephrine. Many recognize this biological process as the “fight or flight” response that takes place in our sympathetic nervous system. From an evolutionary perspective, this response was first adapted to increase an animal’s survival when confronted by an immediate danger. However, Sapolsky argues that humans tend to trigger this stress response psychologically, without any presence of a threatening stimulus. This “artificial” stress response is constantly being activated, which becomes severely taxing on our body’s resources, and later in life can result in some very undesirable outcomes.

All vertebrates have this “fight or flight” response and therefore experience stress. When Sapolsky was in his 20s he traveled to East Africa to study wild baboons. He found that the same area in the brain that correlates with human stress also correlates with baboon stress. Sapolsky then spent the next 30 years observing these baboon communities – their behavior, environment, and social structures. He determined the relation of these factors to stress through the use of blood samples and other physiological measures.

One of the key findings made during Sapolsky’s research was the effect of social hierarchy on stress levels. Dominant male baboons were shown to have much lower levels of stress than subordinate baboons. Sapolsky observed the bigger, dominant males often teasing the weaker ones, pushing them around and not letting them have a fair share of food or mating privileges. In fact, the baboons that were most submissive to the dominant males revealed brain activity similar to the kind found in clinically depressed humans.

Sapolsky’s findings with baboons echoed an important study done on human stress called the Whitehall Study. Researchers decided to record the prevalence of cardiovascular disease and mortality rates of British civil servants between the ages of 20-64. They found that individuals employed closest to the bottom of the business hierarchy (such as messengers or doorkeepers) had a mortality rate that nearly tripled the rate of administrators and CEOs. Since everyone in Britain receives the same quality healthcare this study made important implications into the role of social hierarchy on stress and its effect on the risk of heart disease.

So how does this hierarchical structure contribute to different levels of stress? Researchers theorize that this could be due to a lack of control. The less control we have over our actions the more we are likely to feel stressed out. The same is true for baboons as it is in humans. This idea will be revisited later once I go over some solutions to overcoming stress. Before that I will elaborate further on the health implications of this growing stress epidemic that the whole world is quickly falling victim to.