What vitamin deficiency causes flat warts?

There is a certain association between the occurrence of flat warts and vitamin deficiency, although flat warts are not directly caused by vitamin deficiency. Flat warts are mainly caused by skin infection with human papillomavirus (HPV) and are a type of wart, commonly occurring on the face, back of the hands, forearms, and other areas. Deficiencies in vitamin A and vitamin D may increase the incidence of flat warts or exacerbate their symptoms. Vitamin A plays an important role in skin growth and maintaining skin health and is an essential nutrient for skin cells. Vitamin A deficiency can lead to excessive keratinization and thinning of the skin, potentially increasing the risk of developing flat warts. Vitamin D is also one of the key factors in maintaining skin health. Its deficiency can cause dry, itchy, and inflamed skin and may affect immune function, making individuals more susceptible to HPV infection or worsening existing symptoms. Therefore, although the direct cause of flat warts is viral infection, maintaining adequate levels of vitamins A and D in the body may help prevent the occurrence of flat warts and alleviate their symptoms.