This increases the amount of blood at the surface of the skin allowing it to lose heat – as long as the air is cooler than the body. When the brain senses that the body is warming, the hypothalamus sends messages to blood vessels near the skin, telling to them to dilate. It senses temperature changes, inside the body and out, and makes adjustments to keep it within one or two degrees of 37C. The hypothalamus is the body’s thermostat. Another study linked rising temperatures to higher suicide rates. A recent study in New York found that, on hot days, there were more emergency hospital visits due to substance abuse, mood and anxiety disorders, schizophrenia and dementia. Many people report feeling irritable on hot days, and evidence suggests that extreme heat negatively affects mental health. Proteins and ions accumulate in the brain, causing inflammation. At extremely high temperatures, the blood-brain barrier begins to break down. Hot weather has been linked to reduced cognitive function, judgment errors and higher risk of occupational injury. Studies have shown that extreme heat can affect mental performance.
It can be hard to think clearly when you’re too hot.
