Triggers: The Dogma That Shrinks Lives

The idea of triggers is widely accepted in headache care, but it is rarely questioned.

Patients are told to avoid anything that seems to precede a headache, such as stress, changes in sleep, hormones, weather, certain foods, light, noise, screens, travel, and social events. The list often grows over time.

This idea leads to an unspoken conclusion: If headache keeps happening, it is assumed the patient either missed a trigger or did not control their environment well enough.

But what if this basic idea is actually wrong?

Association Is Not Mechanism

The trigger model is based on timing. Something happens, then a headache starts, so people assume one caused the other.

But just because one thing happens before another does not mean that the first caused the second. In complex systems like the body, events may precede symptoms by coincidence, as a minor contributing factor, or as the final step in a process in which the body was already shifting toward a headache due to underlying sensitivity or dysfunction.

In people with frequent headache or migraine, the nervous system undergoes changes, becoming more sensitive. This increased sensitivity (sensitisation) means that ordinary activities can trigger headache. These events are problematic because the system is predisposed to react, not because the events themselves are inherently harmful.

• Stress does not “cause” migraine in the general population.
• Chocolate does not produce unilateral throbbing head pain in most people.
• Weather changes do not randomly activate trigeminal pathways.

These factors show where someone is vulnerable, but they do not explain why.

The Missing Middle: System Sensitisation

The trigger story focuses on what happened immediately before the pain, but often overlooks the state of heightened nervous system sensitivity that allows these events to provoke headache.

A better way to look at it is with a threshold model. Headache prone individuals typically have a lower threshold for attacks due to nervous system sensitisation, which develops gradually and reflects altered pain processing.

In this context:

• Light is not excessive; sensory gain is elevated
• Stress is not extreme; modulatory buffering is reduced
• Cervical input is not inherently pathological; central responsiveness is amplified

The trigger is just the last thing that pushes an already sensitive system over the edge.

By focusing only on the last step, this model confuses being exposed to something with the real cause of the problem.

When Avoidance Becomes the Treatment

This misunderstanding can have serious effects on patient care.

Patients often respond to trigger education with progressive restriction:

• Dietary elimination
• Social withdrawal
• Reduced physical activity
• Heightened vigilance to internal and external cues

Avoiding triggers does not resolve the underlying problem or help the nervous system return to normal. Instead, it can make people feel more threatened, less able to handle everyday life, and more fragile.

People end up focusing on preventing the next headache instead of working to improve the system that allows headache to happen.

In this way, the trigger model does more than just distract people. It can slowly change how they see themselves and how they act, making them focus on avoiding things.

Triggers as Indicators, Not Enemies

It is more helpful to see triggers as signs that the system is currently sensitive.

Frequent triggering by minor stimuli suggests:

• Elevated central gain
• Reduced inhibitory control
• Lowered physiological tolerance to normal load

When the system becomes less sensitive, patients often notice that things that used to trigger headache do not have the same effect, even if they do not avoid them. This challenges the idea that the trigger was the main cause.

The things people are exposed to did not change. What changed was their system.

Reclaiming Mechanism in Headache Care

This does not mean triggers do not matter. They can help people manage their symptoms when they are more sensitive and notice early warning signs. But triggers should not be the main focus when explaining headache.

When people focus only on triggers, they miss underlying sensitivity and problems with pain control, leading to attempts to control all aspects of life instead of building resilience.

Shift your focus: see triggers as signals, not the main cause. Prioritise improving nervous system resilience over avoidance.

Triggers should not be seen as causes to be afraid of, but as signs that the body’s tolerance is low right now.

A Necessary Shift

If we keep thinking of headache as being caused by everyday things, patients will keep limiting their lives to try to stay in control.

Refocus care: help people rebuild tolerance and resilience, not just avoid life. Centre treatment on strengthening the body’s ability to manage sensory information.

Triggers may still appear in the story of an attack. But they are rarely the author.