Use the right metal material

Look for flat irons that use ceramic, tourmaline or titanium metals. They are the "gentlest on the hair" because they release negative ions that work to tighten the hair's cuticle. This helps your hair look shinier and less frizzy. They also heat more evenly, causing less heat damage to your hair, Moticka says.

On the flip side, be wary of "irons that are ceramic coated or Teflon coated, as they will heat a little more unevenly, and tend to have a more drying effect."

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