Heat causes headaches: why?

Why do hot days seem to trigger recurring headaches in so many people? This is a question that has long intrigued scientists.

Summer headaches are not solely linked to heat. Several environmental factors and lifestyle changes also contribute to this phenomenon, according to some experts.


Studies show a correlation between rising temperatures and headaches. However, heat alone does not explain everything. Dr. Nolan Pearson, a headache specialist at Cedars-Sinai Medical Center, emphasizes the importance of examining other factors.

In summer, air quality often deteriorates. Hot air promotes the formation of ozone, a harmful gas, and other pollutants. These elements can trigger headaches in sensitive individuals. Increased exposure to light, particularly UV rays, complicates the situation. While intense light is not directly responsible, it can exacerbate headaches in those who suffer from migraines.

Changes in routine also play a crucial role. Dehydration, due to inadequate hydration during hot weather, is a common cause of headaches. Similarly, fluctuations in blood sugar levels, caused by decreased appetite, can also be to blame.

Finally, hot nights often disrupt sleep, which is essential in preventing migraines and other headaches. Insufficient or poor-quality sleep increases the risk of painful episodes.

Why does heat disrupt sleep?

Sleep is closely linked to the regulation of body temperature. At night, our bodies naturally lower their temperature to facilitate deep, restorative sleep. When the environment is too hot, this process is disrupted, making it more difficult to fall asleep and affecting sleep quality.

Additionally, heat can increase the frequency of nighttime awakenings. The body struggles to cool down, preventing it from reaching deep sleep stages, which are essential for physical and mental recovery. Thus, a sleep environment that is too warm can not only delay falling asleep but also disrupt sleep continuity and depth, leading to consequences such as daytime fatigue and increased sensitivity to headaches.