Heat styling includes using a flat-iron, curling iron, hot comb (yes, some still use them), blow dryer and even a hooded dryer. Now, do not come for me about the hooded dryer but there are settings on them so use them and not at the highest setting. Hair dryers that heat up to over 175°C / 257°F and curling irons applied for a minute or longer at 175°C / 257°F can cause water bubbles inside your hair and damage the hair shaft. Those temperatures just look like numbers? Well, water boils at 100°C / 212°F so that should put those earlier temperatures in perspective for you. Excessive heat cooks your hair….period.
All heat styling tools can cause dryness. A heat protectant is necessary each and every time you use a heat styling tool but backing away from using it as often or at all will help.