Chronic stress affects nearly all parts of the body

The biology of stress in your body

Stress is a normal human response that has evolved over millions of years to handle changes or threats in our environment. This article is a helpful overview of the biological basics of this response. While it is not harmful to our physiology in the acute setting, chronic stress can lead to damaging changes in the human body over many years.

Stress and the brain

While an acute stress response is a normal bodily function, the effects of chronic stress can be extremely damaging to the human body. This is particularly true with regard to the brain. This article explores the effects of stress on the human brain, including how chronic stress may lead to psychological conditions such as depression and memory loss.

Stress evolved as a survival mechanism to keep humans alive

Stress activates the “fight-or-flight” response when we face threats. It’s triggered by the hypothalamus, which signals the release of adrenaline and cortisol, heightening awareness and energy. While acute stress helps in short bursts, chronic stress—persistent over time—can harm both physical and mental health, leading to conditions like hypertension, anxiety, or depression.

Our ancient fight-or-flight response may contribute to modern ailments

Many common modern diseases humans struggle with may in fact have their origins in our ancient fight-or-flight stress response. Long-term effects of the stress hormones cortisol and adrenaline—in this case, triggered by things like workplace stressors—can wreak havoc on the delicate internal balance of our organ systems.

How stress affects every organ in the body

If you are a visual learner, this resource is for you. Not only does this article from the World Economic Forum outline the causes of modern stress along with helpful strategies, but they have created an approachable infographic to show exactly how stress manifests throughout our different bodily systems. Pair this visual guide with our other resources to gain a deep knowledge of stress and the human body.

Too little stress can be as problematic as too much stress

Hormesis—mild or moderate stress followed by recovery—helps make us more resilient. A stress expert speaking during this roughly 30-minute CNN special explains that our bodies depend on periodic mental and physical challenges to activate our innate defense mechanisms, spurring cellular repair and regeneration.

The second phase of acute stress: the 'slow' response

The body's reaction to acute stress involves two responses: fast and slow. The first occurs immediately, with the central nervous system triggering the release of adrenaline. The second releases cortisol, which elevates blood sugar and blood pressure and restricts nonessential functions like digestion and the immune system.

Prolonged stress impairs the prefrontal cortex

Burnout isn't just a feeling—it physically affects the brain. Prolonged stress impairs regions of the brain responsible for decision-making, emotional control, memory, and more. It can also lead to chemical imbalances, like reduced dopamine and norepinephrine levels, that worsen these effects.

Stress affects different animals in different, but useful, ways

Animals feel stress when they experience actual dangers—such as a zebra chased by a lion. Humans often feel stress from worries, memories, or even thoughts about problems that may occur in the future. For this reason, animals tend to experience stress in short, intense bursts. Conversely, people can feel stressed for long periods, which can eventually be harmful to their health.

Stress can be contagious—and scientists want to learn more about it

Researchers have shown that being around someone who is stressed can trigger a stress response in your body, such as elevated cortisol levels and elevated heart rate. One way this was recently studied was by having people watch stressful activities, like a recorded job interview or solving challenging math problems, and then sampling hormones in observers' spit.

How do anxiety and stress differ?

This article explains that though “stress” and “anxiety” are often used interchangeably, there are distinct differences between the two. Stress is defined as the body's response to an external trigger and can be classified as acute or chronic. Anxiety, however, tends to be triggered internally by excessive thoughts and judgement. Whereas stress disappears when the trigger is gone, anxiety tends to stick around. If left unchecked, both can escalate into more severe mental health conditions.

Stress-induced hormones contribute to gray hair

When the body experiences stress, the sympathetic nervous system releases the hormone norepinephrine. This hormone prematurely activates pigment-producing cells (melanocytes) in hair follicles, which depletes the hair's ability to retain color over the long run.

Chronic inflammation can cause cellular damage and could lead to cancer

Over time, this cellular defense system can inadvertently damage cells and tissues when it's in this heightened alarm mode over a prolonged period. This occurs because, when immune cells are sent somewhere without a true target, they may attack healthy cells and tissues.

Links between long-term caregiving and chronic stress

This Cleveland Clinic overview suggests that around 60% of people caring for family or loved ones with health conditions will experience burnout. Caregivers prepare meals, help with transportation, administer medications, and perform daily tasks for others, all while managing their own lives. This guide may help readers overcome the guilt or frustration of long-term caregiving to seek alternative options.

A framework for the various potential causes of insomnia

Insomnia typically occurs in people dealing with life stressors and physical or mental health conditions, though the exact cause continues to elude researchers. Generally, the factors can be broken down into external (such as stress, medication, etc.) or internal (neurological) factors.

Human anatomy 101: the body's systems

Human life is made possible by the body's ten major systems, which maintain homeostasis by responding to incoming sensory and biochemical input. Each system must work independently and collaboratively for the body to maintain health and respond appropriately to its internal and external environments. The bones of the skeletal system, for example, give the body its shape and protect organs while also facilitating movement with the muscular system.

The gut microbiome's role in chronic diseases

Research shows that the microbial makeup of one's gut microbiome is associated with chronic diseases ranging from asthma to schizophrenia. Understanding these associations may reveal new ways to prevent or treat chronic diseases. In the meantime, nutritional changes—such as including more dietary fiber and unsaturated fat—appear to be the "most obvious, noninvasive, and immediate" way to alter the gut's microbiota makeup and functions.

Diabetes is a hormonal disorder

Hormones are naturally produced in the body in concert with cell receptors, influencing how cells behave, but diseases that affect hormonal production, including those produced by the pancreas or the thyroid, can upend those processes.

Eating competitions can ruin a stomach's elasticity

Competitive eaters make room for all that food by toying with the stomach's ability to expand and contract. Still, doctors warn that repeated stress can destroy that ability, leading to further issues.

How heatstroke—from overexertion or extreme heat—affects the body

When core body temperature soars to 104 degrees Fahrenheit or higher and remains there for about 30 minutes, it sets off a cascade of problems in the body. Proteins and cell membranes can degrade and begin to leak, potentially leading to liver damage, blood clots, GI tract damage, and organ failure, among other issues.

Prolonged space travel significantly impacts multiple human body systems

Astronauts can lose 20% of their muscle mass after two weeks and 10% of their bone mass after six months in space. Decreased sharpness of eyesight and changes in neural connectivity, brain structure and gut bacteria have also been observed.

How water pressure affects the body

The extreme conditions of the deep sea include increasing amounts of pressure as explorers and organisms descend into its depths. The major danger for both fish and humans is the way pressure changes how body tissues absorb chemical molecules...

Daylight Saving Time is linked to a rise in heart attacks and strokes

Losing an hour of sleep with seasonal time changes is not good for our health and it’s linked to risks for the first couple days of Daylight Saving Time, including a short-term rise in heart attacks and strokes. Scientists theorize these elevated risks are linked to the disruption to the body’s circadian rhythm.

Every organ in a mother's body changes during pregnancy

There's limited real estate inside a mother's body; as the uterus grows both up and out, it shifts other organs to make space. A pregnant woman's body produces hormones to loosen muscles to allow for this expansion. Pregnancy also triggers other changes, including faster breathing to compensate for decreased diaphragm range.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

Grief can trigger broken heart syndrome

Broken heart syndrome—stress cardiomyopathy—involves sudden, intense chest pain that is often mistaken for a heart attack. The condition, which affects part of the heart, briefly interrupts the way the heart pumps blood.

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Use this calculator to find the dollar value of your mental load, from meal planning to coordinating after-school care for your children.

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