Modified and translated by CFJA
Why does itching occur?
In the world, many people are suffering from itchy skin. Itchy skin occurs as one of our bodily defence mechanisms to remove a foreign body when it attaches to our skin. We do not feel an itch on the internal organs – we sometimes have a “stomachache” but never have an “itchy stomach”. Based on modern research, it is proven that pain and itch are transmitted to the brain through different nerves. The nerves that signal itching are called “C-fibres”, and the speed that carries information is slow. In contrast, the nerves that signal pain are called “A-fibres”, and the speed that carries information is fast. Hence, although pain is felt instantaneously through A-fibers, the itch felt by C-fibres is much slower than the pain. The end of the nerve that sends the signals for the itch is very close to the area between the epidermis and dermis, in other words, it is on the surface of the skin. So, when the skin starts to get dry, C-fibres, which normally stay between the epidermis and dermis, start to extend and get closer to the surface of the skin. Since C-fibres become sensitive to external stimulation, even slight friction from clothes can cause itchiness. As the dryness of the skin increases, the itchiness will increase. In that case, applying moisturizer or cream can help reduce it. However, it is important to only use a reasonable amount as it will lower our skin’s natural resistance.
Itchy skin is a sign of a problem in the internal organs
The itchy skin can also be a sign of a problem in the internal organs. Our body secretes a substance that causes itchy skin, beta-endorphin, and a substance that reduces it, dynorphin. When the function of the internal organs diminishes, the balance between beta-endorphin and dynorphin becomes unstable. This is thought to be the mechanism of itchy skin. If it does not stop after cleansing the area, we need to suspect a problem in the internal organ. Similarly, if itchy skin does not stop regardless of taking a bath every day, we need to suspect a decline in the function of the internal organs. Thus, non-temporal treatments should be considered.