3. Highlights and coloring -- Highlights and semi-permanent dyes aren't as damaging as bleach, but they aren't without consequences, Mirmirani says. They can also change the inner structure of the hair, causing a lackluster look and dryness, especially if you frequently color to hide roots or gray hair.

Do highlights damage hair permanently?

Does coloring or bleaching your hair damage it forever — like, forever forever? In short, the general consensus among the celebrity hair colorists I consulted with is that, yes, dying and bleaching your hair permanently alters the integrity of your hair.

How long do foils last in your hair?

For foil highlights, you should go back to the salon every 6-8 weeks to keep your colour tidy and easy to maintain.