What is stress?
Any intrinsic or extrinsic stimulus that evokes a biological response is known as stress. The compensatory responses to these stresses are known as stress responses. Based on the type, timing and severity of the applied stimulus, stress can exert various actions on the body ranging from alterations in homeostasis to life-threatening effects and death. In many cases, the pathophysiological complications of disease arise from stress and the subjects exposed to stress, those that work or live in stressful environments, have a higher likelihood of many disorders. Stress can be either a triggering or aggravating factor for many diseases and pathological conditions. In this study, we have reviewed some of the major effects of stress on the primary physiological systems of humans.
A natural reaction
Have you ever found yourself with sweaty hands on a first date or felt your heart pound during a scary movie? Then you know you can feel stress in both your mind and body. This automatic response developed in our ancient ancestors as a way to protect them from predators and other threats. Faced with danger, the body kicks into gear, flooding the body with hormones that elevate your heart rate, increase your blood pressure, boost your energy and prepare you to deal with the problem. These days, you’re not likely to face the threat of being eaten. But you probably do confront multiple challenges every day, such as meeting deadlines, paying bills and juggling childcare that makes your body react the same way. As a result, your body’s natural alarm system the “fight or flight” response may be stuck in the on position. And that can have serious consequences for your health.
How does stress affect the heart?
people who are under intense stress often seem to dramatically keel over from a heart attack, but that’s extremely rare. The real danger is the accumulated impact of chronic stress, which contributes to each of the top five risk factors for developing heart disease: abnormal cholesterol levels, diabetes, high blood pressure, obesity, and smoking.
How does stress affect the brain?
Chronic stress can make your brain behave in an Alzheimer’s-like manner. Stress adversely affects a key structure in the brain, the hippocampus, leading to impaired memory and problems with orientation and sense of direction. These brain changes may have evolved to protect against the memory of traumatic and stressful events, like being attacked by a predator; but losing short-term memory hinders today’s brain-intensive lifestyle. We all recognize the frustration of forgetting where we put our keys, names of people we just met or other recent events. Nor does stress help you function any better on brain-intensive tasks. In one study, scientists studied brain blood flow while subjects performed tasks that required sorting large amounts of data essentially stressful multitasking. They found that the prefrontal cortex, the “executive” part of the brain used for planning, execution, reasoning, and organization, was initially very active but then tired and shut down. That left the “reptilian” brain, the impulsive and emotional brain, in charge. Pay attention to how your emotions transform in the midst of multitasking, typically moving from initial clarity to confusion and frustration.
How does stress disrupt sleep?
When you’re continually stressed, your body constantly pulses out stress hormones, which make it harder to fall asleep and impair the deepest stages of sleep. That can lead to hyperarousal insomnia a state where your mind and body are easily woken by sounds or by your own stressful thoughts. No longer can you sleep as soundly as a baby.
Does stress make you age faster?
One study compared a group of women caring for disabled children with a group of women whose children had no disabilities. In particular, the researchers compared their telomeres, protective sections of DNA that are known to be a genetic marker for aging. Telomeres routinely wither and get shorter with time, but external factors, including stress, can accelerate this process. The study found more prominent premature aging in the high-stress mothers caring for disabled children. In fact, it translated into that group being 10 years older at a cellular level than the other group, who were the same chronological age. The 35-year-old stressed mothers looked closer to 45.
Even short-lived, minor stress can have an impact. You might get a stomach-ache before you have to give a presentation, for example. More major acute stress, whether caused by a fight with your spouse or an event like an earthquake or terrorist attack, can have an even bigger impact. Multiple studies have shown that these sudden emotional stresses especially anger can trigger heart attacks, arrhythmias, and even sudden death. Although this happens mostly in people who already have heart disease, some people don’t know they have a problem until acute stress causes a heart attack or something worse.
When stress starts interfering with your ability to live a normal life for an extended period, it becomes even more dangerous. The longer the stress lasts, the worse it is for both your mind and body. You might feel fatigued, unable to concentrate or irritable for no good reason, for example. But chronic stress causes wear and tear on your body, too. Stress can make existing problems worse. In one study, for example, about half the participants saw improvements in chronic headaches after learning how to stop the stress-producing habit of “catastrophizing,” or constantly thinking negative thoughts about their pain. Chronic stress may also cause disease, either because of changes in your body or the overeating, smoking and other bad habits people use to cope with stress. Job strain high demands coupled with low decision-making latitude is associated with increased risk of coronary disease, for example. Other forms of chronic stress, such as depression and low levels of social support, have also been implicated in increased cardiovascular risk. And once you’re sick, stress can also make it harder to recover. One analysis of past studies, for instance, suggests that cardiac patients with so-called “Type D” personalities characterized by chronic distress face higher risks of bad outcomes.
What you can do
Reducing your stress levels can not only make you feel better right now but may also protect your health long-term. In one study, researchers examined the association between “positive affect” feelings like happiness, joy, contentment and enthusiasm and the development of coronary heart disease over a decade. They found that for every one-point increase in positive effect on a five-point scale, the rate of heart disease dropped by 22 percent. While the study doesn’t prove that increasing positive affect decreases cardiovascular risks, the researchers recommend boosting your positive effect by making a little time for enjoyable activities every day.
Altogether, stress may induce both beneficial and harmful effects. The beneficial effects of stress involve preserving homeostasis of cells/species, which leads to continued survival. However, in many cases, the harmful effects of stress may receive more attention or recognition by an individual due to their role in various pathological conditions and diseases. As has been discussed in this review, various factors, for example, hormones, neuroendocrine mediators, peptides, and neurotransmitters are involved in the body’s response to stress. Many disorders originate from stress, especially if the stress is severe and prolonged. The medical community needs to have a greater appreciation for the significant role that stress may play in various diseases and then treat the patient accordingly using both pharmacological, medications and/or nutraceuticals, and non-pharmacological, change in lifestyle, daily exercise, healthy nutrition, and stress reduction programs, therapeutic interventions. Important for the physician providing treatment for stress is the fact that all individuals vary in their response to stress, so a particular treatment strategy or intervention appropriate for one patient may not be suitable or optimal for a different patient.
American Psychological Association, American Psychological Association, www.apa.org/helpcenter/stress.
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“Lower Stress: How Does Stress Affect the Body?” About Heart Attacks, www.heart.org/en/healthy-living/healthy-lifestyle/stress-management/lower-stress-how-does-stress-affect-the-body.
“Stress Symptoms: Physical Effects of Stress on the Body.” WebMD, WebMD, www.webmd.com/balance/stress-management/stress-symptoms-effects_of-stress-on-the-body#1.
Wilson, Donielle. Stress Remedy: Master Your Body’s Synergy and Optimize Your Health. Empowering Wellness Press, 2013.