Both acute and chronic stress can negatively impact health and wellbeing. However, they do so in different ways. Acute stress is short-lived and often caused by specific events, while chronic stress persists over longer time periods and can result from ongoing life circumstances or health conditions.
What is Acute Stress?
Acute stress is the body’s immediate reaction to a perceived threat, challenge or demand. When acute stress is triggered, the body activates the sympathetic nervous system, releasing stress hormones like adrenaline and cortisol. This speeds heart rate, dilates pupils, tightens muscles, increases blood pressure and boosts energy supplies. It primes the body to respond swiftly to danger – to either fight or flee. Think of it as hitting the accelerator.
Common acute stressors include:
- Experiencing or witnessing trauma
- Being in an accident
- Receiving bad news
- Having conflict with others
- Public speaking
- Rushing to meet a deadline
The intensity of acute stress depends on the demands of the event and an individual’s ability to cope and adapt. A life-or-death situation causes very severe acute stress. But even small daily hassles and frustrations can trigger milder forms. Acute stress symptoms include:
- Pounding heart
- Tight chest
- Sweating
- Headaches
- Upset stomach
- Difficulty concentrating
These responses enable strength and stamina for immediate “fight-or-flight” response. But when the threat passes, the parasympathetic nervous system kicks in to reverse these effects and calm the body down. Blood pressure drops, heart rate slows, muscles relax. This brings the body back into balance.
What is Chronic Stress?
Chronic stress is persistent emotional or physical pressure that continues over an extended time period. It’s akin to revving your car engine high in one gear. Common chronic stressors include:
- Ongoing work or relationship problems
- Long-term caregiving
- Living in poverty
- Trauma from abuse, neglect or disaster
- Grieving
- Chronic illness
- Discrimination
When stressors like these are unrelenting and feel unmanageable, the body keeps secreting stress hormones. This leads to wear and tear that erodes long-term health. Chronic stress symptoms include:
- Persistent sadness or worry
- Trouble sleeping
- Digestive issues
- Weight changes
- Aches, pains and tense muscles
- Low energy and libido
- Skin problems
- Memory issues
Acute vs Chronic Stress: Key Differences
| Acute Stress | Chronic Stress |
|---|---|
| Short-term | Long-term |
| In response to immediate demands | In response to ongoing demands |
| Quickly resolves when demand passes | Persists for months or years |
| Mobilizes energy for “fight-or-flight” | Wears down mental and physical reserves |
| Often thrilling or exciting | Feels unrelenting and depleting |
While acute stress can be adaptive in the short run, chronic stress is mentally and physically exhausting over time. Let’s explore why.
How Acute Stress Affects the Body
When faced with an acute stressor, the hypothalamus signals the adrenal glands to secrete stress hormones adrenaline and cortisol. Adrenaline increases breathing, heart rate, blood pressure and metabolism to provide energy to muscles. Cortisol releases sugar into the blood for extra fuel. The pupils dilate, the lungs work harder and blood vessels constrict to shuttle oxygen to vital organs. This revved-up state prepares the body to immediately confront a challenge.
Once the stressful event ends, the parasympathetic nervous system calms the firing of neurons and lowers stress hormone levels so the body can return to normal functioning. Heart rate, breathing and blood pressure decrease. If the body can regularly restore equilibrium after acute stress, no harm is done. In fact, some acute stress can help build emotional resilience and confidence to handle future demands.
Short-Term Benefits of Acute Stress
- Boosts motivation and alertness
- Improves ability to react swiftly
- Focuses attention on immediate priorities
- Mobilizes energy and strength
- Increases self-confidence when threat passes
However, if acute stress is very intense, frequent or managed poorly, it can be damaging. Let’s look at why.
Risks of Severe Acute Stress
- Reduces ability to accurately assess situations
- Impairs concentration and decision-making
- Increases risk of depression and trauma
- Triggers heart arrhythmias
- Worsens asthma and inflammatory bowel disease (IBS)
Very high levels of stress hormones from frequent or severe acute stress have toxic effects. Over time, this can harm body tissues, increase disease risks and suppress immune function. Additionally, dwelling on upsetting events prolongs stress responses and makes it hard for the body to fully calm down.
How Chronic Stress Affects the Body
Chronic stress stems from challenges that persist without relief. This constant activation of the stress response wears down the body over months and years. It’s like repeatedly stepping on the gas without letting up.
Exposure to stress hormones adrenaline and cortisol is helpful in the short run. But when these hormones are overproduced on an ongoing basis, they suppress functions needed for long-term health.
The constant flood of adrenaline keeps blood pressure, heart rate and metabolism elevated around the clock. This strains the cardiovascular system and causes arrhythmias, heart attacks and strokes. Cortisol increases glucose in the bloodstream while suppressing the immune system. This increases risks for diabetes, infections, slow wound healing, autoimmune diseases and inflammation.
Chronic stress also impacts brain function, digestion, fertility, libido, skin health and many other processes. Let’s examine some key effects.
Effects of Chronic Stress on the Body
- Digestive system – stomach ulcers, IBS, diarrhea
- Cardiovascular system – hypertension, increased heart disease risk
- Endocrine system – impaired insulin production, increased diabetes risk
- Reproductive system – lowered fertility and sex drive
- Nervous system – headaches, depression, anxiety, insomnia
- Immune system – more frequent colds and infections
Let’s look closer at how chronic stress alters brain function and mental health.
Chronic Stress and the Brain
The amygdala is the brain’s threat detector. It signals the hypothalamus to initiate stress responses. Acute stress activates the amygdala briefly. But chronic stress causes amygdala overactivity, leaving the brain in a constant state of “fight or flight” readiness.
This impairs executive functions needed to manage stress well. Thinking flexibility declines, making it harder to solve problems or see alternative perspectives when faced with challenges. Chronic amygdala arousal also suppresses activity in the prefrontal cortex, the brain region that regulates emotions, decision-making and impulse control. This exacerbates feelings of fear, anxiety and irritability.
Additionally, ongoing amygdala signaling depletes serotonin and other neurotransmitters that regulate mood. This contributes to depression, sleep troubles, appetite changes, cognitive impairment and low motivation characteristic of chronic stress.
Is Acute or Chronic Stress Worse?
Both acute and chronic stress negatively impact health, but via differing mechanisms and durations. Acute stress causes immediate physiological changes to mobilize the body’s resources for swift reaction. Chronic stress triggers longer-lasting biological alterations that accrue damage over months and years.
Mild or moderate acute stress generally causes no lasting harm. In fact, it can help build resilience when the body regularly restores equilibrium after dealing with intense demands. However, severe or prolonged acute stress impairs functioning in the moment and increases risks for stress-related diseases.
Chronic stress exerts damaging effects by keeping the body in a constant state of hormonal imbalance and hyperarousal without recovery periods. This cumulative strain on bodily systems leads to accelerated aging and susceptibility to disease.
Let’s summarize some key differences:
Key Differences Between Acute and Chronic Stress
| Acute Stress | Chronic Stress |
|---|---|
| Short-lived | Ongoing for months or years |
| Fight-or-flight response | Constant hyperarousal and hormonal imbalance |
| Often exciting or thrilling | Feels depleting, demoralizing |
| Benefits can outweigh risks | Accumulates gradual damage to health |
| Peaks and dissipates quickly | Grinds away persistently |
For immediate threats or challenges, acute stress can mobilize the resources and alertness needed to manage the situation. But chronic stress often feels like running a marathon without rest – the constant demand saps vitality and frays psychological well-being over time.
Conclusion
Acute stress arises from demands or events in the moment. It mobilizes the body’s energy reserves via the fight-or-flight response. Mild acute stress can be energizing and even beneficial when the body restores equilibrium afterwards. But severe or prolonged acute stress can impair functioning.
Chronic stress stems from ongoing demands like relationship conflicts, financial strain or caregiving burdens. The unrelenting physiological arousal and hormonal imbalance wear down mental and physical health over months and years. Chronic stress is worse than acute stress due to its cumulative damage, persistence and harmful health consequences.
The keys to mitigating both forms of stress are establishing healthy coping strategies, supportive relationships, relaxation practices, balanced lifestyles and professional help when needed. Learning stress management skills ultimately enables more resilience, productivity and well-being in both the short and long run.