Causes of Migraine: Genetics, Brain Changes & Triggers

Migraine doesn't have one confirmed cause. It's currently understood as a neurological condition rooted in genetics and changes in brain and nerve activity, with attacks set off by a personal mix of triggers — things like stress, hormonal shifts, poor sleep, certain foods, or weather changes. No single factor explains every case, and researchers still don't fully understand why the brain reacts this way.

That combination of biological predisposition plus everyday triggers is why two people with migraine can have completely different attack patterns.

The Biological Basis: What's Happening in the Brain

During a migraine attack, nerve cells in and around the blood vessels of the head become overactive. This activity releases inflammatory substances and pain signals, which is why migraine involves both nerve and vascular changes even though the underlying driver is neurological, not purely vascular.

Researchers still don't know exactly why this activation happens in some people and not others. What's clearer is that different parts of the brain go through measurable changes during an attack — including swelling, inflammation, release of certain proteins, and heightened sensitivity to light, sound, or touch.

[REVIEWER: add clinical insight here — for example, how you explain the neurological versus "just a headache" distinction to patients newly diagnosed with migraine.]

Genetics: Why Migraine Runs in Families

Family history is one of the strongest known risk factors for migraine. More than half of people with migraine have at least one close relative who also has it, though there isn't a single, predictable inheritance pattern for most cases.

Genetic research has identified regions of the genome linked to migraine risk across neurological, vascular, and hormonal pathways, suggesting many genes each contribute a small amount of risk rather than one gene causing the condition outright.

A rare exception is familial hemiplegic migraine, a form that runs in families and has been linked to specific mutations in genes such as CACNA1A, ATP1A2, and SCN1A — all involved in how nerve cells manage ion channels. These specific mutations are not thought to play a meaningful role in typical, common migraine, which affects far more people.

Hormones and Sex-Related Factors

Migraine is markedly more common in women than men, and ovarian hormones are thought to be a major reason why. Fluctuations in estrogen around menstruation, ovulation, pregnancy, and menopause are commonly reported triggers, which is part of why many women notice a link between their cycle and attack frequency.

Common Migraine Triggers

Triggers don't cause migraine on their own — they act on an already-susceptible brain. Still, identifying and managing them is one of the most practical tools available. Commonly reported triggers include:

Lifestyle and routine changes

• Missed meals or fasting

• Too much or too little sleep

• Overexertion or intense physical activity

• Dehydration

Diet and substances

• Alcohol, especially red wine

• Caffeine — both consumption and withdrawal

• Aged cheese, cured meats, and foods containing nitrates or certain preservatives

• Artificial sweeteners

Environment and senses

• Bright or flickering lights

• Loud noises

• Strong odors, such as perfume or petroleum products

• Weather or barometric pressure changes

Stress and emotional factors

• Emotional stress, both during and after a stressful period

• Anxiety

Medical factors

• Certain medications

• Overuse of acute migraine medication, which can itself trigger more frequent headaches

[REVIEWER: add clinical insight here — for example, how you help patients distinguish a genuine trigger from a coincidental pattern when reviewing a headache diary.]

Why Triggers Are Different for Everyone

A food or situation that reliably triggers one person's migraine may have no effect on someone else. Researchers describe migraine as arising from a combination of genetic, environmental, and lifestyle factors that differs from person to person, which is why no universal trigger list applies to everyone equally. This is also why elimination diets or blanket avoidance strategies don't work the same way for all patients.

Risk Factors Beyond Genetics and Hormones

A few other factors are consistently associated with higher migraine risk or frequency:

• Age: Migraine often begins in adolescence or early adulthood.

• Sex: Migraine is roughly two to three times more common in women than men.

• Family history: Having a close relative with migraine raises personal risk.

• Other health conditions: Depression, anxiety, and sleep disorders are commonly associated with migraine, though the relationship is complex and not fully understood.

Tracking Your Own Triggers

Because migraine causes are individualized, a headache diary — noting food, sleep, stress levels, weather, and menstrual cycle alongside attack timing — is one of the most useful tools for identifying personal patterns. Bringing this record to a healthcare provider can help narrow down realistic, evidence-based changes rather than guesswork.

FAQ

Is migraine genetic or caused by lifestyle? Both. Genetics create an underlying susceptibility, while lifestyle and environmental factors — like sleep, diet, and stress — act as triggers for attacks in people who already have that susceptibility. Neither factor alone fully explains migraine.

Can stress alone cause a migraine? Stress is one of the most commonly reported triggers, and the drop in stress after a tense period ("letdown migraine") can also trigger attacks. However, stress typically triggers migraine in someone already predisposed rather than causing it outright.

Why are migraines more common in women? Hormonal fluctuations, particularly in estrogen linked to menstruation, pregnancy, and menopause, are believed to play a major role. This is a key reason migraine affects roughly two to three times more women than men.

Are migraine triggers the same for everyone? No. Triggers vary significantly between individuals, which is why researchers point to a personalized combination of genetic, environmental, and lifestyle factors rather than a single universal cause.

Can certain foods cause migraine? Some people report attacks linked to foods like aged cheese, alcohol, or products with certain preservatives, but this varies by individual. A headache diary can help identify whether a specific food is a genuine trigger for you.

Takeaway

Migraine isn't caused by one thing — it's a neurological condition shaped by genetics and set off by a personal mix of triggers. Understanding both halves of that equation, and tracking your own patterns, is often more useful than chasing a single "cause" to avoid.