No, Kojic acid does not cause stretch marks. In fact, Kojic acid is often used in skincare products to help reduce the appearance of hyperpigmentation, such as dark spots or melasma. It is a natural ingredient derived from certain fungi and works by inhibiting the production of melanin in the skin. Stretch marks, on the other hand, are caused by the stretching and tearing of the dermis layer of the skin, usually due to rapid weight gain, pregnancy, or growth spurts. While Kojic acid can help lighten dark spots, it does not have any direct effect on the formation or prevention of stretch marks.