Genes aren't the only factor affecting hair type. The environment can also have a big impact on hair, especially the texture. Humidity can make the hair frizzy or curly, whereas cold winter air can make hair dry and frizzy. Hair texture also changes with age. Hair becomes grey, thinner, rougher, finer, and dry. The oil glands in the scalp shrink with age. Hormones and certain medications also can temporarily or permanently change your hair's characteristics. How you treat and style your hair can change its texture. Bleaching, hair coloring, using styling tools, straightening, and perming can change hair texture.