At a recent editors' dinner to celebrate the launch of ghd Platinum, ghd's newest straightener, we were all hit with one big revelation—there is a *precise* temperature at which you should be straightening your hair. And yes, it's a Goldilocks situation: Too low, and your hair becomes dull and lifeless. Too high, and you can fry your hair—and even cause irreversible damage. (Eeep!)
So what's ideal temperature? According to researchers, 365°F is what you want your flat iron to be. That temperature allows the most styling benefits in the fewest strokes, helping hair retain moisture and easily sealing the cuticle—which leaves your locks shiny, smooth, and resistant to humidity.
Lower than this, and you'll likely be making several passes to get the same effect, thereby drying out your hair and leaving it lackluster. A higher temp is just unnecessary heat, and once you reach 420°F you can create a lot of problems, since this is the temp where keratin protein starts to melt—something you can't repair. (Translation: breakage and split ends.)
To make sure you have your hair game on point, buy an adjustable iron and set it to 365—and never, ever change it. You're welcome.