Dandruff is like dirt on your clothes: it’s not a serious disease, but it can be embarrassing, irritating, and hard to get rid of completely. Most of the time, it’s not necessary to go to the hospital for dandruff (unless there are symptoms such as redness, swelling or severe itching of the scalp), and a good anti-dandruff shampoo can make the situation better. However, facing the colorful bottles and jars on the supermarket shelves, we inevitably have various questions about the promotion and advertising slogans of these products: Is anti-dandruff shampoo really effective? Which one is the best to use? Will there be any side effects? To answer these questions, let’s start with the “head”. Dandruff: the result of disrupted normal function Dandruff is the keratinocytes shed by the scalp. Under normal circumstances, keratinocytes are shed so rarely and slowly that they are not visibly visible. However, when stimulated in some way, immature keratinocytes are produced in large numbers, clumped together and shed, forming a “snowflake” phenomenon known as dandruff. Electron microscope scan of human dandruff Dandruff is very common. According to a survey, nearly half of the population has dandruff problems during prepubescence. Dandruff generally does not require medical attention, but if the symptoms are severe or accompanied by redness, swelling and itchiness of the scalp, it may be seborrheic dermatitis or other diseases, and it is then necessary to seek medical diagnosis and treatment. In the process of dandruff formation, two substances play an important role: 1. the oil secreted by the scalp; 2. the fungus that feeds on the oil. In fact, these two substances are not inherently harmful. Normal human scalp cells secrete oil; fungi are also present on the surface of everyone’s skin and are harmless under normal circumstances. However, under certain conditions, for example, during puberty when oil secretion is high, fungi may multiply on the surface of the scalp, stimulating scalp cells to secrete more oil; the large amount of oil provides nutrients for further expansion of fungi. Eventually, the original normal scalp keratin layer cell metabolism becomes unstable, immature keratin cells gather and fall off, and dandruff is produced. Fungi: overgrowth causes dandruff Fungi are tiny organisms invisible to the naked eye, and there are many kinds. One of them is called Malassezia, which grows mainly on the skin surface of animals and humans. Malassezia need oil to grow, so they are mostly concentrated on the scalp, face and other areas where sebaceous glands are densely distributed. Although Malassezia is present in almost everyone, studies have found that people who develop dandruff symptoms have 1.5-2 times more Malassezia on the surface of their scalp. At the 22nd World Congress of Dermatology, Shell editors interviewed Rene Rust, PhD, of the University of Basel, Switzerland. He believes that the fungal overgrowth and reproduction stimulates the scalp cells, leading to heavy oil production and is responsible for dandruff production. Studies have shown that Malassezia produces a number of by-products in the process of breaking down oil and providing nutrients to itself, one of which is oleic acid. Oleic acid penetrates beneath the cuticle of the scalp. If you have a sensitive skin type, the oleic acid triggers an inflammatory response and the result is irregular cracks in the scalp cuticle, which in turn produces dandruff. Thus, dandruff = overgrown fungus + abnormal secretion of oil -> mass production of keratinocytes. To treat it, we must go to the root cause. Anti-dandruff: Inhibiting fungus is the only way The current medical treatment for dandruff mainly adopts the strategy of inhibiting the growth of fungus and bringing the number of fungus back to the normal level. The common means of treatment is to use shampoos with antifungal function . For the treatment of severe dandruff or seborrheic dermatitis, hospitals offer special shampoos for the treatment. Common antifungal drugs available today include zinc hydroxypyrithione (ZPT), ketoconazole, and Piroctone ethanolamine salt (Octopirox). For ordinary people, these seem to be some chemical terms that can only be heard in hospital pharmacies. In fact, major brands of anti-dandruff shampoos apply several of these anti-fungal ingredients, and they have similarities in principle and active ingredients compared to the therapeutic shampoos sold in hospitals. For example, ZPT is the anti-dandruff ingredient used by most brands such as Hefeiffer; Octopirox is used in some of L’Oreal’s products. (Ketoconazole is a banned substance in the cosmetic hygiene code, and shampoos with ketoconazole added are drugs and can only be purchased at pharmacies.) For most patients with dandruff, as long as the other symptoms mentioned at the beginning of the article do not occur, it is generally not necessary to go to the hospital, and shampoos with anti-dandruff functions are sufficient to deal with them. Moreover, these anti-dandruff shampoos are more comfortable to use than therapeutic shampoos. A shampoo with a good experience can help patients stick with it for a longer period of time while maintaining its efficacy. Also, since all shampoos contain different drug ingredients and levels, you may need to try several before you find the product that works best for you. Washing your hair: cleanliness is the most crucial and gentle hands In addition to antifungal as a treatment, it is also important to keep your hair clean and wash away excess oil and gathered keratinocytes for dandruff prevention and control. For people who have dandruff troubles, doctors recommend that they should wash their hair with an appropriate shampoo every day. In addition, scalp with dandruff problems may sometimes be itchy, but it should not be scratched. This is because scratching, as a physical stimulus, can make the scalp produce more oil and aggravate dandruff symptoms. This also applies to washing your hair: be gentle and reduce the irritation to your scalp. Some people may complain that “they have more dandruff after using anti-dandruff shampoo”. This phenomenon may be due to the fact that their scalp is prone to dryness and peeling, and some anti-dandruff shampoos can aggravate the dryness of the scalp. The solution is also very simple: after shampooing with anti-dandruff shampoo, use scalp care products to moisturize the scalp, which will improve.