Flat Iron Heat Protectant Usage

Heat protectant spray
Photo: Valerii Meleshko/Shutterstock
Q: I straighten my hair with a flat iron every day. How often should I use heat protectant? Should I use it every day, even when it has been used the day before without washing it out?
A: Generally speaking, you want to use your protectant product every time you plan to use heat styling techniques.
If your protective product is one that can build-up on the hair or leaves an oily or greasy residue, then you may want to get a second product that is lighter and suitable for daily use between shampoos.
Just remember that the hair needs to be dry before you pass it through a flat iron, and therefore, you will be using more than just a flat iron, unless you apply the product and allow the hair to dry naturally afterward.
I also want to take the time to remind you that while you only need to shampoo the hair when it is soiled or dirty, you should condition the hair daily. Even the normal environment outside and inside can have an effect on the hair.
Going from a humid, hot outside in Summer to cool and dry interior climates (as well as going from cool, moist interiors to hot, dry exteriors - depending on where you live) can leech the moisture out of the hair faster than you might expect. Since the effects of such environs are cumulative, the hair runs a risk of significant damage without daily moisture.
See also:
Heat styling basics
How often you can use hair straighteners
How badly will straightening damage my hair?
What is the best thermal protectant spray for flat iron straightening?