Stress is a natural reaction that helps the body decide what to do when a situation requires action. “Fight or flight” is the normal response when we are confronted by a threat that is dangerous or potentially life-threatening, either real or perceived. The body gets flooded by adrenaline, which allows us to quickly decide what to do. Once the threat is removed, adrenaline levels return to normal and our body is quickly stabilized. This is one of the perfectly normal effects of stress.
Chronic effects of stress
When stress become chronic, however, the body never quite returns to its resting state. Perched on the edge of a reaction, the effects of stress can be profound and very damaging, leading to long-term chronic illness including pain and cardiovascular disease. Stress does not just affect the body. The brain can also experience changes due to long-term, chronic stress.
Stress affects memory
Researchers at The Ohio State University have found that stress can affect short-term memory, specifically in mice who were repeatedly confronted by a larger, more aggressive mouse. Mice were placed in a maze that they had previously mastered and then joined by an aggressive mouse. Even though the study mice knew where the exit was, the presence of the nasty intruder confused them and caused them to “forget” how to leave the maze.
In addition to this, the mice experienced measurable inflammation in their brains that researchers believe was caused by an immune system response to stress. The inflammation was largely centered in the hippocampus, which is also the area linked to anxiety and depression.
Mice that were removed from the stressful situation exhibited inflammation and signs of stress and anxiety up to a month after the experiment. John Sheridan, who worked on the study and is associate director of Ohio State’s Institute for Behavioral Medicine Research, pointed out that the brain does not easily forget the effects of stress on the brain, noting:
“Stress releases immune cells from the bone marrow and those cells can traffic to brain areas associated with neuronal activation in response to stress. They’re being called to the brain, to the center of memory.”
If stress causes inflammation in the brain, as found in this study, it stands to reason that this inflammation could further exacerbate existing pain conditions or facilitate the rise of new ones. Those people with autoimmune disorders may be particularly susceptible to stress in this way.
Stress affects self-control
The phenomenon of stress eating whereby you devour an entire box of cookies or a bag of chips after a stressful situation now has a measurable cause: stress alters the connections in the brain that relate to self-control.
Study participants underwent a stressful situation in the laboratory (immersing their hand in an ice water bath for three minutes) and were then asked to choose a food. These volunteers were all trying to maintain a healthier lifestyle. In the study, stressed participants were more likely than the control group to select unhealthy foods
Researchers pinpointed altered connections between the amygdala, striatum, and the dorsolateral and ventromedial prefrontal cortex as the culprits for this decrease in self-control but also indicated that more research is needed.
Senior author Todd Hare pointed out that even mildly stressful events had this effect:
“This is important because moderate stressors are more common than extreme events and will thus influence self-control choices more frequently and for a larger portion of the population.”
Lack of self-control can affect diet and lifestyle choices like exercise and consumption of alcohol, all of which can negatively impact those with pre-existing chronic conditions.
Stress affects the heart
Towards the end of the 20th century, research into and treatment of heart disease centered mainly on men, resulting in a steady decline of fatal heart attack among men. While this is great news, of course, the other side of the coin is that heart disease in women has been largely ignored, due in part to the fact that women with heart disease exhibit much different symptoms than men.
Turns out, women’s hearts are actually more sensitive to stress than men’s, resulting in a sharp increase in fatal heart attacks in women in the last two decades.
To make matters worse, heart disease in women is often more difficult to detect. Alexandra Kautzky-Willer, professor for gender medicine of MedUni Vienna, pointed out that:
“In case of cardiovascular disorders, women have a different age distribution, other clusters of risk factors and the vascular changes in the heart also differ morphologically. Furthermore, the diagnosis and therapy are often more difficult: Examinations such as ECG or ergometry are less conclusive…In case of acute coronary syndrome, women often suffer from a non-obstructive, functional coronary artery disorder and, in case of cardiac failure, a dysfunction of the filling function of the heart at preserved output performance in comparison with men.”
In other words, the effects of stress on the body, specifically, women’s hearts, is subtle, occurs at a different rate than the accepted demographic for men, and has no specific treatment protocols.
Other effects of stress on the body and brain
Chronic stress affects every other system in the body, including:
- Respiratory system: Stress causes rapid breathing that, over the long-term, can actually make breathing more difficult for those with asthma or emphysema.
- Digestive system: Stress causes your liver to produce more glucose. If the stress does not recede and the body cannot balance itself, there is a risk of developing Type 2 diabetes. Additionally, stress affects the way the body digests food and may cause diarrhea or constipation.
- Muscles: Chronic stress causes tight, sore muscles. Over time this can become chronic pain that is unrelieved by treatment.
- Reproductive system: Over time, stress causes testosterone production to drop in men, potentially causing erectile dysfunction. In women, chronic stress can disrupt the menstrual cycle and compromise fertility.
For short-term stress, we need our bodies to react quickly. Long-term effects of stress on the body and brain can cause chronic, potentially fatal illness. Learning how to handle stressful events is important and could potentially save your life!