Science

How inflammation actually works

The immune cells and signalling proteins behind every case of inflammation, from a paper cut to a chronic condition.

This page is general education, not a diagnosis. If you're dealing with persistent or severe symptoms, please see a doctor — lifestyle tracking can be a useful complement to medical care, never a substitute for it.

It starts as a defence

When your body detects an injury, infection or irritant, immune cells release signalling proteins called cytokines, which trigger the classic signs of inflammation — redness, heat, swelling and pain — as blood flow increases and immune cells move toward the site.

The cast of characters

Several cell types are involved: mast cells release histamine, which widens blood vessels; neutrophils arrive first to attack pathogens directly; macrophages clean up debris and coordinate the wider response. Cytokines — including well-studied ones like IL-6 and TNF-alpha — act as the messengers coordinating all of this.

Acute inflammation resolves

In a healthy acute response, once the threat is cleared, a separate set of signals actively "turns off" inflammation and returns tissue to normal — inflammation isn't just switched on, it's supposed to be actively resolved afterward.

Where chronic inflammation comes from

Chronic, low-grade inflammation happens when this resolution process doesn't fully complete, or when something — diet, poor sleep, excess alcohol, chronic stress, inactivity — keeps low-level immune signalling active in the background, without an acute injury to explain it. This is the state THE FAD's five pillars are all, in different ways, aimed at reducing.

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