What is Stress?

The technical definition of stress is the body’s nonspecific response to any demand – pleasant or unpleasant.

People have very different ideas with respect to their definition of stress. Probably the most common is, “physical, mental, or emotional strain or tension.” Another popular definition of stress is, “a condition or feeling experienced when a person perceives that demands exceed the personal and social resources the individual is able to mobilize.”

Most people consider the definition of stress to be something that causes distress. However, stress is not always harmful since increased stress results in increased productivity. A definition of stress should also embrace this type of healthy stress, which is usually ignored when you ask someone about their definition of stress.

Any definition of stress should also include good stress, or eustress. For example, winning a race or election is just as stressful as losing, or more so. A passionate kiss and contemplating what might follow is stressful, but hardly the same as having root canal work. Any definition of stress should similarly explain the difference between eustress and distress.

The definition of stress for most people tends to focus on the negative feelings and emotions it produces. Almost every definition of stress also discusses certain resultant physical, physiological or biochemical responses that are experienced or observed. A very comprehensive definition of stress that includes these and more is the biopsychosocial model, which, as it name suggests, has three components. This definition of stress distinguishes between an external element, another that is internal, as well as a third that represents the interaction between these two factors.

The total negative response from distress can be divided into three phases: the alarm reaction, resistance, and then exhaustion. When individuals are exposed to a stressor, they are, at first, taken off guard. Then, they attempt to resist the change, and eventually fall victim to exhaustion in countering the stressor.


of mothers feel stressed in their homes

Acute Stress

Fight or flight. The body prepares to defend itself. It takes about 90 minutes for your metabolism to return to normal when the response is over.

Chronic Stress

The cost of daily living: bills, kids, jobs, etc. This is the stress we tend to ignore or push down. Left uncontrolled this stress affects your physical health.


Stress in life, such as getting married, having a baby, winning money, getting promoted, making new friends, or graduating, that has positive connotations.


Stress in life, such as experiencing divorce, punishment, injury, negative feelings, financial problems, or work difficulties, that has negative connotations.

Stress in America

Lingering memories of the COVID-19 pandemic, global conflicts, cries of racism and racial injustice, inflation, and perceived climate-related disasters continue to weigh heavily on the collective consciousness of Americans.

The national public health emergency surrounding COVID-19 officially ended on May 11, 2023. Although many have celebrated a return to “normal,” findings from the latest Stress in America™ survey suggest a more complex reality. According to psychologists from the American Psychological Association (APA), the perception of normalcy is overshadowing the posttraumatic effects that have significantly altered our mental and physical health.

Upon reviewing this year’s survey data, APA psychologists unanimously agreed that our society is experiencing the psychological impacts of collective trauma. “The COVID-19 pandemic created a shared experience among Americans. While the early-pandemic lockdowns may seem like a distant memory, their aftermath lingers,” said Arthur C. Evans Jr., PhD, APA’s chief executive officer.

The report “Stress in America 2023: A Nation Recovering from Collective Trauma” examines the lasting psychological impacts of these significant crises. Analysis of mental and physical health pre- and post-pandemic reveals signs of collective trauma across all age groups.

The data indicates that the long-term stress sustained since the onset of the COVID-19 pandemic has significantly impacted well-being, with a notable rise in chronic illnesses—particularly among those aged 35 to 44, increasing from 48% in 2019 to 58% in 2023. This age group also saw the highest increase in mental health diagnoses, from 31% in 2019 to 45% in 2023, though adults aged 18 to 34 reported the highest rate of mental illnesses at 50% in 2023.

Prolonged stress poses risks for various mental health challenges, heightens sensitivity to daily stressors affects overall life outlook and goals, and impacts the body’s physiological stress response, with significant implications for physical health. Coping with long-term stress requires distinct strategies compared to temporary stressors.

Ongoing stress keeps the body on high alert, leading to inflammation, immune system wear, and an increased risk of ailments such as digestive issues, heart disease, weight gain, cancer and stroke.

“We cannot ignore that we have been profoundly changed by the loss of more than one million Americans, and the shifts in our workplaces, schools, and culture at large. To move towards posttraumatic growth, we must first identify and understand the psychological wounds that persist,” stated Evans.

We are facing a national mental health crisis that could yield serious health and social consequences for years to come.

The Science of Stress

We must differentiate between distress, which often conveys harmful stress, and eustress, which often conveys overwhelming happiness. During both distress and eustress, the body undergoes virtually the same responses to various negative or positive stimuli; however, eustress causes much less damage than distress. Therefore, how an individual experiences stress influences how well they adapt to change.

It’s worth noting, stress diseases are caused by errors in the body’s adaptation process. They may be avoided when the body’s regulatory processes are properly checked and balanced and adaptation is facilitated by improved perception and interpretation.

Lewis Coleman, MD’s Landmark Discovery in the Science of Stress

Lewis Coleman, MD, Chief Science Officer at The American Institute of Stress

Dr. Lewis Coleman’s groundbreaking research has revolutionized our understanding of stress, revealing its complex biochemical mechanisms and their profound effects on human health. His landmark discovery underscores the pivotal role of stress in chronic diseases, offering new pathways for treatment and prevention. This pivotal work not only enhances scientific knowledge but also paves the way for innovative therapeutic strategies to mitigate the impact of stress on our lives.

Woman reading a magazine about the Lewis Coleman Story

If You're Looking for Answers, You Have to Ask the Right Questions.

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