Why does the heat in the city affect the body so much?
Why can even an ordinary walk feel like a serious physical effort on a hot day? Why do you just want to lie down after working in the heat, while your concentration becomes worse?
It is not only about the high air temperature. In an urban environment, heat puts additional stress on the body, especially when it persists for several days.
Let’s look at why this happens, who should be particularly careful, and which simple measures really help make hot days easier to tolerate.
Why is heat harder to tolerate in the city?
Asphalt, concrete, cars, and buildings absorb heat during the day and slowly release it at night. This phenomenon is known as the urban heat island effect.
As a result:
- in some cities, temperatures in densely built-up areas can be several degrees higher than in the suburbs;
- the body does not have enough time to recover at night;
- the strain on the body’s thermoregulation system increases.
This is why even a relatively “ordinary” temperature of 30–32°C can feel significantly harder to tolerate in a city.
Dehydration develops faster than you might think
Relying only on intense thirst is not always reliable: especially in children and older adults, the sensation of thirst may appear later.
We lose both water and electrolytes through sweating.
This can lead to:
- weakness;
- headache;
- muscle cramps;
- reduced concentration;
- low blood pressure.
How does heat affect the heart and blood vessels?
When the air temperature rises, the body activates its natural cooling mechanisms: the blood vessels in the skin dilate and sweating increases.
This helps release excess heat, but at the same time requires additional work from the cardiovascular system:
- the heart may beat slightly faster;
- blood pressure may decrease;
- insufficient fluid intake can sometimes cause weakness or dizziness.
Most healthy people adapt easily to these changes.
However, people with cardiovascular conditions, such as heart failure, significant hypertension, or heart rhythm disorders, should pay closer attention to how they feel during hot weather and follow their doctor’s recommendations.
Overheating affects the brain too
Even moderate dehydration and overheating can affect how you feel: fatigue develops, concentration becomes more difficult, and exhaustion sets in faster.
This is one of the reasons why the number of road traffic accidents and occupational injuries increases during the summer.
Heat exhaustion can progress to heat stroke
Early signs include:
- severe weakness;
- dizziness;
- nausea;
- rapid pulse;
- headache.
In most cases, the body can cope with heat on its own. However, sometimes overheating becomes severe and requires medical attention.
Particularly concerning symptoms include:
- confusion and loss of consciousness;
- speech disturbances;
- seizures;
- very hot skin, sometimes without sweating.
This is a reason to call emergency medical services immediately.
Sun affects more than just temperature: how to protect your skin in summer
Even if you are not planning a beach holiday, your skin is exposed to ultraviolet radiation every day in the city.
UV radiation does not feel like heat, but it is associated with accelerated skin photoaging, pigmentation, cellular skin damage, and an increased risk of developing certain types of skin cancer with prolonged exposure.
It is important to remember: sunscreen is not only for holidays or sunny days.
How can you protect your skin properly?
- Use sunscreen with SPF 30 or higher, especially if you spend a lot of time outdoors.
- Apply a sufficient amount of sunscreen approximately 15–20 minutes before going outside, and reapply it after prolonged sun exposure, swimming, or heavy sweating.
- Do not forget additional measures: a wide-brimmed hat, sunglasses, and clothing that covers the skin.
Some medications can make heat more dangerous
Many people do not know that some medications can affect the body’s ability to regulate temperature or maintain fluid balance.
For example:
- certain diuretics;
- some psychotropic medications;
- medications with anticholinergic effects.
Do not stop your treatment on your own. However, if you take such medications, it is worth discussing with your doctor in advance how to manage them during hot weather.
Food poisoning is more common in summer
In summer, it is especially important to pay attention to food storage: high temperatures accelerate the growth of microorganisms.
Sometimes just a few hours in the heat are enough for food to become unsafe.
5 simple rules that can help you cope with the heat more easily
1. Drink water regularly
Do not wait until you feel very thirsty. It is better to drink small amounts throughout the day.
If you sweat heavily or engage in physical activity, your fluid requirements increase.
2. Avoid being outdoors during the hottest hours
This is usually between 11 a.m. and 5 p.m.
If you need to go outside: stay in the shade, wear a hat, and use sunglasses.
3. Wear appropriate clothing
It is better to choose:
- light colors;
- loose-fitting clothes;
- natural or modern “breathable” fabrics.
4. Do not overexert yourself
Whenever possible:
- move workouts to early morning or evening;
- avoid heavy physical work during the day.
5. Keep your indoor environment cool
Even an ordinary fan can help, but in extremely high temperatures it may no longer be effective.
If possible, use air conditioning or spend several hours in cool places such as shopping centers, libraries, or air-conditioned public spaces.
However, it is still worth avoiding extreme temperature contrasts, so do not turn the room into a “freezer.”
Summer can still be comfortable in the city
The body can adapt to high temperatures, and small changes in everyday habits can make summer days in the city more comfortable.
The main thing is to pay closer attention to how you feel and remember: heat becomes much easier to tolerate when we understand how it affects the body and how we can help it.