The Cost of Constant Vigilance

The stress response is a masterpiece. It marshals the whole body around a single question — stay alive — and then, ideally, releases. When release is prevented, when the environment (or the interpretation of the environment) keeps signalling threat, the machinery stays engaged. This is not a philosophical problem. It is a biological one, and its cost is measurable.

Framing chronic vigilance as personal weakness has cost people decades of their lives. Framing it as biology invites the response biology deserves — recovery, connection, environmental change, and, when needed, care.

Bruce McEwen introduced the concept of allostasis — stability through change — and its price, allostatic load: the cumulative wear on the body when adaptive systems remain activated beyond what conditions require. McEwen (1998, 2007) documented how the mediators of allostasis — cortisol, catecholamines, inflammatory cytokines, and others — do their jobs in the short term and contribute to disease in the long term. Cardiovascular, metabolic, immune, and cognitive systems all bear part of the price. Contemporary work (see Guidi and colleagues’ systematic review, 2021) has operationalised allostatic load as a multi-system composite and shown its association with a wide range of chronic conditions, from cardiovascular disease to depression to premature mortality. The scale of the effect makes clear that constant vigilance is not a lifestyle choice — it is a biological state with clinical consequences.

Recent research has extended the framework in two important directions. First, it has clarified that allostatic load is modifiable: reducing exposure to stressors, restoring social connection, sleep, and regular physical activity all lower the composite. Second, it has emphasised that early-life stress can bias the system toward higher baseline load in adulthood — not deterministically, but as a probability shift that later intervention can reduce.

Chronic vigilance is expensive. The intervention is not “relax more” but “change the conditions the nervous system is reading as unsafe”. That may be relational, environmental, financial, or medical. The nervous system is not a mood; it is a barometer, and it will keep reading until conditions change.

**“I can push through.”** You can, and many do. The cost does not disappear; it distributes itself into the body across years. **“Stress makes people stronger.”** Acute, recoverable stress does. Chronic, unrecoverable stress does the opposite — well documented.