Eating more soy sauce will not darken your skin. Soy sauce is a seasoning made from soybeans and has the appearance of a brown liquid that enters the human intestine to be digested into substances needed by the body. The pigmented substances contained in soy sauce are not directly transferred to the skin because they do not have the function of synthesizing melanocytes, but are excreted from the body with the body’s metabolites. Human skin color is determined by genetics as well as by one’s own melanin, and cannot be changed by diet. Melanocytes in human skin are responsible for synthesizing melanin and maintaining skin color, and the more melanocytes there are, the darker the skin tone. The number of melanocytes is directly related to genetics, and some people are born with a darker skin tone. In addition, frequent sun exposure can also lead to a darker skin tone. Melanocytes are active under ultraviolet light and can produce too much melanin. Soy sauce is a commonly used condiment, rich in sodium ions, which can increase the freshness of dishes, but excessive consumption of soy sauce may cause an increase in blood pressure, especially in patients with high blood pressure should avoid consuming too much soy sauce to avoid aggravating the disease.