With the exception of conditions such as dandruff, interest in the scalp is relatively low. However, when we consider the scalp as part of the skin, interesting observations can be made. The average amount of sebum secretion in the scalp varies depending on sex. Several studies show differences in scalp characteristics among races, but in some cases, these are difficult to find. The scalp has a weaker barrier function than does facial skin. The reason for the weak barrier function is unclear, but it is necessary to consider the effect of dandruff on the scalp. Growth of dandruff-related bacteria weakens the barrier. However, strengthening the barrier suppresses dandruff. In other words, there is an interdependency between scalp bacteria and skin, which is important for the maintenance of scalp barrier homeostasis. Anxiety regarding a sensitive scalp is as high as that for sensitive skin. At least 40% - 50% of individuals in modern society have complaints such as itching due to a sensitive scalp. The sensitivity of the scalp is similar between races. This is not a skin disease, but we have to think about how problems that customers face can be solved. Skin barrier and sensitive scalp are closely related. Collectively, strengthening or lowering the effect on the scalp barrier may result in a healthy scalp environment. As a result, it will alleviate people’s complaints about the scalp.
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