Hair is made up of a protein called keratin. When hair is healthy, the keratin strands are smooth and aligned, which allows light to reflect off the hair shaft and give it a shiny appearance. However, when hair is damaged, the keratin strands become rough and uneven, which causes light to scatter and gives the hair a dull appearance. Damaged hair is also more likely to tangle and break, which can lead to pain when the hair is moved.
There are many things that can damage hair, including heat styling, chemical treatments, and environmental factors such as sun exposure and pollution. To avoid damaging your hair, it is important to use gentle hair care products and to limit the use of heat styling tools. You should also protect your hair from the sun and pollution by wearing a hat or scarf when you are outdoors.