[Kim Jaeho's Life Story]<183> Visually Appealing Skin and Healthy Skin

If you had to choose between good-looking skin and healthy skin, which would people choose? We can easily find many people around us who are more interested in good-looking skin. Because the condition and complexion of the face are very important in social life, more and more people are investing money and time generously in skincare. Reflecting the high interest in good-looking skin, the global skincare market size is expected to grow annually by 4.4% from approximately 162 trillion won in 2018 until 2025.

If good-looking skin were also good for health, then focusing solely on skincare would be enough, but good-looking skin does not guarantee skin health. Skin diseases are among the most common human health problems, with the World Health Organization (WHO) estimating that they affect nearly 900 million people. There are hundreds of types of skin diseases, and many symptoms are similar, making it difficult to distinguish which disease is causing the symptoms.

All diseases require finding and addressing the cause to be cured, but since there are many types of skin diseases, their causes are diverse and often not precisely known, making it difficult to eliminate all causes. To prevent and heal skin diseases, it is necessary to consider not only the skin but also other tissues or parts that may cause skin diseases. This is because the cause of skin diseases often lies outside the skin.

To find the causes of skin diseases, it is necessary to understand the skin ecosystem. About one million invisible microorganisms live in 1㎠ of skin, including 1,000 types of bacteria, yeasts, fungi, viruses, protozoa, and mites. Most of these do not harm the skin but maintain a symbiotic relationship with it, helping skin health as beneficial microorganisms.

Beneficial skin microorganisms help skin health by competing with harmful skin microorganisms for nutrients or by secreting chemicals harmful to them, preventing harmful microorganisms from settling on the skin. They also induce natural immune responses that cause skin cells to produce their own antibiotics to kill bad microorganisms. This is why the microorganisms living in the skin ecosystem are important for skin health.

The skin provides a good environment for beneficial microorganisms living in the skin ecosystem to maintain a balanced symbiotic relationship. The skin naturally maintains an acidic pH of 4 to 5.5, providing comfort to beneficial microorganisms and discomfort to harmful ones. If this balance is disrupted for some reason, diseases can occur or worsen easily. For example, if antibiotics reduce beneficial bacteria, yeasts may overgrow, disrupting the microbial balance and making it easier to be infected by harmful bacteria.

Most skin diseases are closely related directly or indirectly to the immune system, so understanding the immune system well and maintaining strong immunity is also important for preventing and healing skin diseases. Diseases caused by problems with immune cells can be divided into three types.

First, diseases caused by weak immunity. These are infectious diseases where immune cells fail to properly eliminate pathogens causing skin diseases, including viral infections like measles or shingles, bacterial or fungal infections, and melanoma caused by immune cells failing to remove cancer cells on the skin.

Second, autoimmune diseases caused by errors in immune cell recognition functions, where immune cells attack normal skin cells that should be protected, such as psoriasis or systemic lupus erythematosus (lupus). Third, allergies where immune cells overreact to harmless substances (allergens) like pollen or eggs, including urticaria and atopic dermatitis.

Wouldn't it be the best of both worlds if healthy skin also looked good? When managing skin to create good-looking skin, there is something you must always remember. Skincare should be done in a way that creates an environment the skin likes, and care must be taken not to disrupt the balance of the skin ecosystem or confuse the immune system (see Life Story episode 68). Attention should be paid to the "hygiene hypothesis," which explains the phenomenon of increasing allergy patients as society becomes more hygienically clean.

Kim Jaeho, Independent Researcher

This content was produced with the assistance of AI translation services.