Many of us like to apply henna in our hair to change the color of the hair or to hide the white hair. Henna has hidden natural properties, which can color your hair. At the same time, some people apply henna in summer to keep the head cool. Applying medi can benefit the hair in many ways (is henna safe to use on hair). But can leaving henna on hair for a long time can also cause many types of damage to your hair.