What Triggers Migraines? The Most Common Causes and How to Spot Yours

You felt the familiar throb start behind one eye, and now you're asking the question almost everyone with migraine eventually asks: what did I do to cause this? Maybe it was the wine last night, the skipped lunch, the storm rolling in, or a stressful week that finally caught up with you. The honest answer is reassuring once you understand it: migraines are rarely set off by one single thing.

Migraine triggers are the internal and external changes that can tip a sensitive brain into an attack. Some are within your control, some aren't, and most people have a personal handful rather than a universal list. Here's what the evidence actually says about what triggers migraines, why combinations matter more than any one culprit, and how to start spotting your own.

What is a migraine trigger?

A migraine trigger is anything that can set off an attack in a person who is already prone to migraine. It's important to understand the difference between a cause and a trigger. Migraine is a neurological condition, and the underlying tendency is built into how your nervous system responds to change. A trigger doesn't create migraine out of nowhere; it nudges an already-sensitive brain past its threshold.

This is more common than many people realize. Roughly 39 million people in the United States live with migraine, and the population prevalence has stayed stable for about 30 years at 11.7% to 14.7% overall. So if you're trying to track down what's setting yours off, you're in very good company.

The most common migraine triggers

The American Migraine Foundation identifies a top 10 list of migraine triggers. In order, they are:

• Stress (one of the most frequently reported triggers of all)
• Changes in or an irregular sleep schedule, including too much or too little sleep
• Hormonal changes, especially around menstruation
• Caffeine and alcohol
• Changes in weather and barometric pressure
• Diet, including skipped meals
• Dehydration
• Bright or flashing light
• Strong smells
• Medication overuse

Why it's usually a combination, not one thing

Here's the part that trips most people up. Often a combination of triggers, not a single factor, sets off an attack. You might tolerate a glass of wine on a well-rested, low-stress evening, but the same glass after a short night and a skipped meal could push you over the edge. That's why the same trigger seems to "work" some days and not others.

This is also why the commonly blamed food triggers, the so-called 'C's of cheese, citrus, chocolate, coffee, and cola, are so confusing. They're widely reported by patients, but they have not been conclusively confirmed as consistent triggers by scientific studies. A food may genuinely set off your migraines, or it may simply have coincided with several other triggers stacking up at once.

Hormones and weather: two triggers that hit differently

Hormonal changes are a major, female-specific trigger, and they help explain a striking pattern: migraine is roughly three times more common in women than men. Prevalence runs about 17.1% to 19.2% in women versus 5.6% to 7.2% in men, and women make up about 75% of people with migraine. The drop in estrogen around menstruation is thought to increase CGRP release, alter serotonin metabolism, lower the pain threshold, and promote cortical spreading depression, the wave of brain activity behind migraine. This is why some people get reliable attacks right before or during their period.

Weather is the trigger people most want to blame and can least control. Changes in barometric pressure can set off migraine in some people, along with bright sunlight and glare, extreme heat or cold, high humidity, dry air, and windy or stormy weather. Since you can't change the forecast, the practical strategy is to tighten up the triggers you can control, like sleep, hydration, and meals, on days when the weather is working against you.

How to identify your personal triggers

Because triggers stack and vary from person to person, guessing rarely works. The recommended method for pinning down your own is a headache diary. The idea is simple: each time an attack starts, log what was happening around it.

Track things like when the attack started, what you ate and drank, how much you slept, your stress level, where you were in your menstrual cycle, the weather, and what finally relieved the pain. Over a few weeks, patterns tend to surface that no single bad day would ever reveal.

• When the attack started (time and date)
• What you ate and drank, and whether you skipped a meal
• How much you slept the night before
• Your stress level and any major events
• Where you were in your menstrual cycle, if relevant
• The weather that day
• What relieved the pain and how long the attack lasted

When to see a doctor

Identifying triggers is powerful, but it's not a substitute for medical care, especially if migraines are frequent, severe, or changing. Seek prompt medical attention for a sudden, severe "worst headache of your life," a headache with fever, stiff neck, confusion, weakness, numbness, trouble speaking, or vision loss, or a headache after a head injury. These can signal an emergency rather than a typical migraine.

It's also worth seeing a clinician if you're relying on pain relievers more than a couple of days a week, since medication overuse is itself a recognized trigger that can lock you into a cycle of more frequent headaches. A clinician can confirm the diagnosis, rule out other causes, and build a prevention and treatment plan around your specific triggers. If it's hard to get to an in-person visit, a clinician-overseen telehealth option like Nolla can be a convenient starting point for a personalized plan.