The effects of intense heat on the skin.

During a heatwave, the temperature tends to remain above 33°C for several consecutive days. This increase in temperature promotes perspiration. As a reminder, this natural phenomenon carried out by the body helps to regulate body temperature. It manifests itself through the production of sweat by the sweat glands in order to maintain the body temperature around 36 and 37°C.

When the body produces sweat, it expels a significant amount of water, which can lead to the epidermis becoming dehydrated. Furthermore, the body loses both water and minerals, substances that are essential for maintaining skin health. To counteract this dehydration during periods of heat, it is necessary to regularly drink water and hydrate the skin using moisturising treatments.

Heat rashes, also known as miliaria crystallina or sudamina, are characterised by the formation of numerous tiny bumps gathered on a part of the body. They can itch and form in the summer during the rise in temperature. They are formed when the sweat naturally produced by the body for regulation accumulates and does not properly evaporate.

When the skin perspires, sweat is produced by the sweat glands and expelled through the pores. Produced in excess due to heat, it mixes with sebum and impurities accumulated on the epidermis. As a result, this mixture of sweat and impurities clogs the pores and makes the expulsion of sweat difficult. These remain trapped under the epidermis and lead to the formation of heat bumps.

Dermatitis is a specific issue that frequently affects the skin during periods of heat. It presents itself as a skin rash of red patches followed by itching. This heat-induced rash primarily occurs on parts of the body that are covered by clothing.

The cause is the overproduction of sweat, the accumulation of heat, and friction against clothing. To avoid friction against skin covered in sweat, it is recommended to wear loose clothing made from natural fabrics.

This type of targeted issue manifests itself through the swelling of the ankles, feet, and hands. It is a swelling of the tissues that typically occurs in individuals not acclimatised to heat. Once affected by peripheral oedema, the skin easily indents when you press on it. It may take some time before the skin begins to tighten again.

The swelling of soft tissues at the extremities is caused by the dilation of blood vessels due to heat. Consequently, water moves beneath the skin, resulting in swelling. This specific issue is also known as water retention.

The dilation of blood vessels does not only bring about negative effects. Indeed, blood circulation becomes more fluid, which soothes muscle pain.