Stress, and what it does to the body

People presenting with palpitations, gut symptoms, headaches and chest tightness are frequently told that it is "just stress", which is both true and one of the least helpful things a person can be told.

The acute response

A threat activates the sympathetic nervous system within seconds: adrenaline release, raised heart rate and blood pressure, redirected blood flow, dilated airways, sharpened attention, suspended digestion.

Shortly after, a slower hormonal cascade releases cortisol, which mobilises glucose and sustains the response.

This is a well-designed system for a short, physical emergency, and it resolves through a feedback loop once the threat passes.

Why chronic stress is different

The system was built for events with an ending.

Sustained activation — a job, a caring responsibility, financial insecurity, an unresolved conflict — keeps the response partially switched on, and the feedback that would shut it down becomes less effective.

The downstream consequences are documented across systems: raised blood pressure, altered glucose handling, changes in immune function including impaired wound healing and reduced vaccine response, disturbed sleep, and effects on appetite and fat distribution.

Chronic stress is also associated in cohort studies with cardiovascular events, though disentangling it from behaviour — smoking, drinking, inactivity, poor sleep — is genuinely difficult.

The symptoms people present with

All of these are physical consequences of a physiological state, not imagination.

Palpitations and awareness of the heartbeat.

Chest tightness and breathlessness, which frequently causes the fear of a cardiac event, which worsens the symptoms.

Gut symptoms: nausea, urgency, cramping, altered bowel habit — the gut–brain axis being a well-established two-way pathway.

Tension headaches and jaw pain from clenching.

Muscle tension and back pain.

Dizziness and tingling, frequently from altered breathing.

Skin flares of eczema, psoriasis and acne.

Frequent minor infections.

And menstrual irregularity, since the reproductive axis is suppressed by sustained stress.

Which does not mean these should be assumed to be stress — the reason to see a clinician is that several have other causes that need excluding.

What reduces the physiological load

Interventions with reasonable evidence.

Physical activity, which is the most consistently supported, and which appears to blunt the reactivity of the stress response rather than merely distracting from it.

Slow breathing, particularly with a longer exhalation, which shifts autonomic balance measurably within minutes and is the only intervention here that works during an acute episode.

Sleep, which both suffers from and amplifies stress.

Mindfulness-based stress reduction, which has a reasonable trial base for perceived stress and for several stress-related conditions, with effects that are real and moderate rather than transformative.

Social connection, which is consistently protective in the epidemiology.

Time outdoors and in green space, where the evidence is observational but consistent.

And reducing alcohol and caffeine, both of which amplify the physical symptoms while appearing to help.

Control, which matters more than load

A finding that recurs across occupational research.

The relationship between demands and health is strongly modified by how much control a person has over how the demands are met, and by whether support is available.

High demand with high control is stimulating; high demand with low control is the combination associated with harm.

Which explains why two people with identical workloads have entirely different outcomes, and why interventions that give people some agency outperform those that simply teach coping.

The interventions that do not work

Worth naming.

Being told to relax.

Stress management training delivered to individuals while the organisational causes are unchanged, which the occupational health literature is fairly clear about.

Cortisol testing in saliva sold direct to consumers, which is difficult to interpret without clinical context and does not lead to useful action.

And supplements marketed as adaptogens, where the evidence is generally small, short and industry-funded.

When to seek help

When physical symptoms are new, severe or unexplained, which need assessment regardless of the suspected cause.

When stress is producing persistent low mood, anxiety or hopelessness.

When alcohol or other substance use is increasing.

When it is affecting the ability to work or to care for others.

And when it has become the permanent background condition rather than a response to something identifiable, which is the point at which it stops being manageable alone.

General information only, not medical advice. Consult a qualified clinician about new or persistent physical symptoms rather than assuming they are stress.