San Antonio Express-News (Sunday)
How stress can damage the body and mind
We all know what stress feels like. Some people experience shakiness or a racing heart; others develop muscle tension, headaches or stomach aches. But what we might not realize is that our physiological responses to life’s stresses and strains can have deeper, less obvious, repercussions for just about every organ and system in the body.
“I think people really underestimate just how big the effects are,” said Janice KiecoltGlaser, director of the Institute for Behavioral Medicine Research at Ohio State University College of Medicine.
When you experience stress, your brain triggers the release of hormones that produce physiological changes. These changes, called the stress response or the fight-or-flight response, are designed to help people react to or cope with threat or danger.
The trouble is that these changes can occur in response to stressors that are not lifethreatening — work deadlines, traffic jams, financial pressures, family strife — and over time, they can take a toll on the body and mind, said Kiecolt-Glaser.
What follows is a look at how stress can affect many organs and systems in the body.
The brain: Acute forms of stress — a work deadline or argument — can be beneficial in the short term, briefly bathing the brain with hormones (such as cortisol) that help improve motivation, ability to focus and performance, according to Wendy Suzuki, a professor of neural science and psychology at New York University and author of “Good Anxiety: Harnessing the Power of the Most Misunderstood Emotion.”
By contrast, the prolonged elevated cortisol levels that come with chronic stress and post-traumatic stress disorder can interfere with and damage the brain’s hippocampus, which is critical for long-term memory, Suzuki said. Long-term increases
in cortisol also can damage the brain’s prefrontal cortex, which is essential for focused attention and cognitive processes that allow you to plan, organize, solve problems, engage in flexible thinking and control impulses.
The cardiovascular system: With acute stress, the heart rate increases and blood pressure surges so you can prepare to fight or run for your life. After the encounter subsides, these functions are supposed return to normal. But that doesn’t always happen in the modern world, where we can encounter stressor after stressor.
Chronic stress, which occurs over months to years, can lead to high blood pressure, adiposity (fat accumulation), insulin resistance and greater systemic inflammation, explained Ahmed Tawakol, co-director of the Cardiovascular Imaging Research Center and director of nuclear cardiology at the Massachusetts General Hospital and Harvard Medical School. “Together, these drive the buildup of arterial plaques and heighten the risk of heart attack and stroke.”
Over time, stress also can lead to narrowing of blood vessels
and heightened coagulation (blood clotting), which further raise the risk of cardiac events.
The respiratory system: During a stressful situation, the sympathetic nervous system ramps up and stress hormones are released, which leads to rapid respiration. “Shallow, rapid breathing is not a good thing — you’re not getting rid of carbon dioxide optimally and you can starve yourself of oxygen, which can lead to symptoms such as lightheadedness and dizziness,” noted Neil Schachter, a pulmonary specialist at the Mount Sinai Medical Center in New York City.
Both acute and chronic stress can trigger asthma attacks or exacerbate chronic obstructive pulmonary disease in those who have these conditions. A review of studies in a 2017 issue of the journal Respiratory Medicine found that active stressors (completing a math task) and passive stressors (watching stressful movies) both led to increases in activation of the sympathetic nervous system, and the passive form of stress also was associated with mild bronchoconstriction among people with asthma.
The immune system: During a stressful event or period of
time, stress hormones such as cortisol travel to the immune system and have various dysregulating effects. One is by triggering heightened inflammation, which is at the root of many conditions, including cardiovascular disease and dementia, noted Kiecolt-Glaser.
While short-term inflammation usually helps the body heal — think about the swelling around a sprained ankle, enhancing blood flow to the area — too much or chronic inflammation can turn against healthy cells, making you more vulnerable to infection, less responsive to vaccines and slower to heal. What’s more, the release of pro-inflammatory cytokines can travel to the brain and increase the risk of depression. “It’s a nasty cycle,” Kiecolt-Glaser said. “If you’re depressed, you sleep poorly and are less likely to exercise, which can increase inflammation and depression.”
The gastrointestinal system: Stress decreases gastrointestinal motility (slowing emptying of the gut), which can make you feel nauseated, bloated or constipated, explained gastroenterologist Cindy Yoshida of the University of Virginia Health System in Charlottesville.
But the bigger news: Stress leads to changes in the gut microbiome, affecting the diversity of the bacteria, and it affects function in ways that increase leakiness of the gut. This means bacterial byproducts from foods can leak outside the GI tract into your circulation, which sets up inflammatory and hormonal responses, Yoshida explained.
The skin: If you’ve ever experienced a flare-up of acne or eczema when you were stressed, you’re familiar with the effects of stress on the skin, the largest organ in the human body.
“Over the years, we’ve come to realize the skin is a very active organ in its own right — it has its own immune system, and it interacts with the brain in a moment-to-moment fashion,” said Rick Fried, a dermatologist and clinical psychologist and clinical director of Yardley Dermatology Associates and Yardley Clinical Research Associates in Yardley, Pa.
As a result, when you experience acute or chronic stress, the skin’s immune system becomes activated, which promotes inflammation, leading to a worsening of skin conditions.
Stress also can interfere with the skin’s ability to hold onto water — and the cascade of stress hormones prompts the sebaceous glands in the skin to produce more oil, which can trigger breakouts, said Joshua Zeichner, an associate professor of dermatology at Mount Sinai Hospital in New York City.
What to do: For the most part, the damaging effects of stress are somewhat modifiable, experts said. If you exercise regularly, get quality sleep and take steps to reduce or manage stress, “you can reduce stress activity in the brain, systemic inflammation and your risk of developing cardiovascular disease,” Tawakol said.
You also can dial down your reactivity to stress by doing deep breathing exercises, progressive muscle relaxation, meditation, yoga or aerobic exercise, Fried advised.