Heatwave and "brain fog": how extreme heat affects the brain, especially in the elderly

In Oradea, at midday, thermometers showed over 40 degrees, and residents spoke of fatigue, the need to stay in the shade, and a feeling that their minds were working more slowly. This is not merely an impression: specialists confirm that extreme heatwaves genuinely affect brain function.

The brain is the body's largest consumer of energy: although it accounts for only 2% of body weight, it uses approximately 20% of the body's total energy. When body temperature rises, blood is redirected away from the brain towards the skin as a natural cooling mechanism. This process causes what specialists call "brain fog" – difficulty concentrating and a reduced capacity to make decisions.

What doctors say

Hadrian Borcea, chief physician at UPU-SMURD Bihor, explains: "The human body has all manner of protective mechanisms for both heating and cooling. The main organ or radiator of the human body is represented by the blood capillaries."

Carmen Pantiș, a primary care specialist in anaesthesia and intensive care, draws attention to the risks for certain categories of people: "20% of blood flow is necessary for the proper functioning of the human brain. In conditions of extreme heat, there is a tendency in every organism, particularly in elderly patients and those with oncological conditions or heart disease. We recommend staying very well hydrated, avoiding walks in the sun, and being very, very careful with chronic medication."

Symptoms to watch out for

Scientific research shows that heatwaves genuinely alter the brain's chemistry. According to Digi24 journalist Bogdan Băcilă, if you find yourself reading the same paragraph several times without retaining it, forgetting things more often than usual, or feeling more irritable, the explanation may well be the effect of the heat on brain activity, rather than a cause for concern in itself.

How to cool the brain quickly

For effective cooling, doctors recommend applying a damp cloth or simply splashing water on the back of the neck, the wrists, and the temples.