How many saber-toothed tigers have tried to maul you to death today? Hopefully, the stressors in your life don’t involve an apex predator chasing you through the bush, as was the case for our cavemen ancestors. Still, stress affects us the same way it did them. We are wired for stress physiologically much the same way we were millennia ago, with our primordial fight-or-flight response within us keeping us alert and safe.

Though not all stress is bad, we need a break from bad stressors, otherwise our health may begin to deteriorate.

Modern humans battle bad stressors — staying in an unhealthy or challenging relationship; coronavirus; financial hardships; job worries; drug and alcohol abuse — and all this distress may cause the body to:

  • Elevate blood pressure
  • Increase heart rate
  • Slow down digestion and metabolism
  • Flood the bloodstream with chemicals like adrenaline and cortisol
  • Tense up muscles

Though you might not have to flee a predator, the same chemical cocktails are coursing through your body as the caveman's.

Stress and cardiac issues

electrocardiogram and stethoscope Several studies have found links between elevated stress and cardiovascular disease. (Photo: Thitiporn taingpan/Shutterstock)

The link between stress and heart disease isn't totally clear, says the American Heart Association, but being under chronic stress can affect blood pressure and heart rate, which can lead to heart issues. It can also cause many people to "manage" their stress with unhealthy behaviors like drinking and smoking, which can affect heart health.

Several studies have found links between stress and heart health. A study published in the journal BMJ of siblings in Sweden looked at nearly 137,000 people with stress-related disorders compared to more than 170,000 of their brothers and sisters. Researchers found the participants who had a stress disorder had significantly higher rates of heart problems — including heart attacks, cardiac arrest and blood clots — compared to their siblings, who had similar upbringings and genetic makeup, but no anxiety disorders.

Earlier research has shown that people who report high levels of stress — whether due to work or personal reasons — are at higher risk of heart attacks over the course of their lives.

A recent study adds an exclamation point to this news. For some people who survive a heart attack, mental stress — which is increasingly present in the age or coronavirus — may be a stronger predictor of a repeat heart attack or dying from heart disease, according to research presented at the American College of Cardiology's Annual Scientific Session Together with World Congress of Cardiology in March 2020.

Emory researchers compared tests of myocardial ischemia —when blood flow to the heart is reduced so much that the heart muscle doesn't get enough oxygen — to traditional exercise-driven stress tests to see if there were any differences between heart attack survivors. By looking 300 young and middle-aged participants, they found a two-fold increase in likelihood of having another heart attack or dying for those suffering mental stress.

"In our study, myocardial ischemia provoked by mental stress was a better risk indicator than what we were able to see with conventional stress testing," Dr. Viola Vaccarino, the Wilton Looney Professor of Cardiovascular Research in the department of epidemiology at Emory University Rollins School of Public Health and the study’s principal investigator said in the AAC news release.

Stress and memory loss

Remembering and forgetting If you're constantly living a stressful life, you may be causing permanent damage to your memory and brain size. (Photo: Ollyy/Shutterstock)

Cortisol, like adrenaline, helps us deal with stress, but too much of it can be harmful to the body.

Young adults and middle-aged people who experience stress on a regular basis may experience memory loss before they turn 50. An study published in the journal Neurology shows people with high levels of cortisol have impaired memory compared to people with average cortisol levels. These people experience impaired memory years before they show symptoms of long-term memory loss.

Researchers studied 2,231 people with an average age of 49 who didn't suffer from dementia. Their memory and thinking skills and blood samples were tested eight years apart, and those with higher levels of cortisol scored lower on the test. MRI scans showed they even had smaller brain volume.

"Our research detected memory loss and brain shrinkage in middle-aged people before symptoms started to show, so it's important for people to find ways to reduce stress, such as getting enough sleep, engaging in moderate exercise, incorporating relaxation techniques into their daily lives, or asking their doctor about their cortisol levels and taking a cortisol-reducing medication if needed," study author Dr. Justin B. Echouffo-Tcheugu of Harvard Medical School. "It's important for physicians to counsel all people with higher cortisol levels."

Stress and adrenal exhaustion

Stressed out and tired woman working Cortisol helps us deal with stress, but too much of it can lead to adrenal exhaustion, which has a domino effect on the body’s symptoms. (Photo: JUTARAT BUADOK/Shutterstock)

Research has linked cortisol to body fat storage around the abdomen. In turn, piling on the pounds around the belly can lead to heart disease.

Excessive cortisol flooding the bloodstream can lead to adrenal exhaustion. Some doctors believe adrenal exhaustion, when someone is constantly tired, is the main culprit behind every chronic disease. Dr. Lawrence Wilson isn't alone in thinking that the mainstream medical profession often fails to recognize adrenal burnout as a real health concern.

WebMD reports that 75 to 90 percent of all doctor visits are stress-related, but in its assessment of stress on the body, nowhere does it mention adrenal fatigue due to excess cortisol, which is sometimes referred to as the stress hormone.

Failing to cope with bad stress, and thus severely fatiguing the adrenal glands (which rest over the kidneys), has a domino effect on the body’s many functions, including:

  • Hormonal (hormonal pathways can be disrupted)
  • Musculoskeletal (you won’t burn fat as efficiently and gain muscle)
  • Immune (adrenal fatigue from bad stress wreaks havoc on the immune system)
  • Digestive (bad stress slows digestion, chronic digestion problems may arise)
  • Cardiovascular (adrenal fatigue can lead to heart palpitations and other problems)

Stress and obesity

Woman measuring her waist The more cortisol in your body over time, the more likely you are to be overweight and have a thicker waist. (Photo: Monkey Business Images/Shutterstock)

People who suffer long-term stress may also be more prone to obesity, according to a study conducted by University College London researchers and published in the journal Obesity. The research, which involved examining hair samples for levels of cortisol, showed that exposure to higher levels of cortisol over several months is associated with being more heavily overweight and more persistently overweight.

While stress and weight long have been thought to go hand-in-hand (think stress eating and comfort foods), this study confirms the link by examining long-term cortisol levels in more than 2,500 men and women over a four-year period.

"People who had higher hair cortisol levels also tended to have larger waist measurements, which is important because carrying excess fat around the abdomen is a risk factor for heart disease, diabetes, and premature death," lead researcher Dr. Sarah Jackson of UCL said in a press release. "Hair cortisol is a relatively new measure which offers a suitable and easily obtainable method for assessing chronically high levels of cortisol concentrations in weight research and may therefore aid in further advancing understanding in this area."

Stress and weakened immune system

Stressed out guy in his office An unhealthy diet consumed under prolonged stress can weaken your immune system. (Photo: Tigger11th/Shutterstock)

Stress makes your blood vessels dilate, your pupils enlarge, your breathing rapidly increase and your sweat glands kick into overdrive, contributing to adrenal fatigue. Eating an unhealthy diet can also play a role.

How? Eating the wrong foods over many years can break down the mucosal barrier in your gut. Think of the mucosal barrier as the body’s second skin as well as the body’s first line of defense against pathogens, or unwanted nasty critters invading your gut.

Your immune system lies mostly in your gut, so if you have eaten poorly over the years, the integrity of the mucosal barrier system can become severely compromised. In the long run, digestion is compromised. With most of your immune system residing in your gut, your immune system will weaken.

Concerned about what stress has done to your body? Seek a medical professional or alternative health practitioner who understands adrenal fatigue and knows how to restore hormonal pathways. A nutritional approach to battling stress should also be applied.

Editor's note: This story has been updated with new information since it was originally published in September 2011.

What does stress do to the body?
Stress affects us the same way it did our cavemen ancestors. But there are steps we modern humans can take to mitigate it.