Very hot water and scrubbing to remove dirt... The skin suffers.

During the summer when I sweat even while staying still, I take frequent showers, but it is better to avoid taking long showers with very hot water or rubbing the skin with rough towels. Hot water removes skin oils and damages keratinocytes that protect the skin. Especially for people with skin conditions or the elderly, whose skin may lack oils and become more dry, it is recommended to take short showers with lukewarm water.

Incorrect shower habits can also cause dry skin dermatitis (xerotic eczema).

Scratching when itchy can cause wounds and increase vulnerability to bacterial infections such as folliculitis and impetigo. Especially for people with inherently sensitive skin conditions like atopic dermatitis and psoriasis, symptoms can worsen further. Additionally, prolonged exposure to hot water can cause skin blood vessels to dilate and activate mast cells, leading to itching.

Professor Shin Jeong-jin of the Department of Dermatology at Korea University Ansan Hospital advises, "It is best to take a shower with lukewarm water below 40 degrees Celsius for 5 to 10 minutes," and "Applying a moisturizer containing cholesterol, ceramides, and fatty acids within three minutes after showering helps maintain skin health."

Scrubbing the skin repeatedly can damage the stratum corneum, making the skin more prone to dryness and allowing allergens to penetrate easily. Therefore, it is better to use a gentle shower towel or wash lightly with your hands. As you age, sebum secretion decreases, so it is advisable to reduce the frequency of showers to once a day or every two days if you do not sweat excessively.

Professor Shin Jung-jin said, "Mildly acidic body washes help maintain skin oil levels," and "Alkaline products damage the skin barrier and promote moisture loss."