Flat iron or relaxing: which damages your hair more?

Monica questions: What causes more hair loss straightening you hair with a flat iron or doing a relaxer at a salon?

Left Brain straighteners her out:

Great question Monica. A quick answer is that Relaxers lead to more hair loss than Flat Irons. Read on for why. If you want some additional options to flat irons and relaxers take a look at this post we did on 7 ways to straighten hair.

How Hair Straightening Processes Work

While relaxers and flat irons can give you similar styles, they work in completely different ways. To understand how they work, you first must know that hair is made up of proteins. Within these proteins are chemical bonds responsible for hair strength & hair shape. The two most important types include Hydrogen bonds and Disulfide bonds. (There are others but Sarah’s eyes are starting to glaze over so I’ll stop there.)

Hydrogen bonds are weaker, temporary and dependent on the amount of water in your hair. When you flat iron your hair, you remove curls/frizz by first mechanically forcing hair straight and then removing the water with heat. It works just like an iron on clothes. This locks hair into whatever shape it currently is in. It works great as long as your hair stays dry. But once hair picks up moisture from the air, it will start to revert to its more natural shape.

Hair’s natural shape is controlled more by the Disulfide bonds. These permanent bonds don’t depend on how much water is in hair. With relaxers, hair’s disulfide bonds get broken down making your hair permanently straighter. At least permanent until new hair grows back.

Both relaxing and flat ironing damage hair but relaxing is much worse because it actually degrades hair proteins.

3 Kinds of Hair Loss

When you ask about hair loss you could be talking about 3 different kinds; breakage, natural, and permanent. Since I’m not sure which you’ve asked about, we’ll look at all three.

  1. Breakage: Everyone’s hair breaks to some extent, but damaged hair breaks more. Relaxing causes much more damage thus leading to more hair loss via breakage than flat irons.
  2. Natural: People shed just like dogs & cats. Your hair has a natural cycle where you lose about 100 hairs naturally each day. Neither relaxing or flat irons will affect this hair loss. You might notice more hair loss while flat ironing but that just because you pull out hairs that would have fallen out on their own.
  3. Permanent: In this type, hair stops growing at the roots & there is not much you can do to get it to come back. It’s unlikely that flat ironing will cause this but it is possible relaxing hair can. If your scalp is exposed to the chemicals in relaxers for too long, it can burn you and cause permanent hair loss. This isn’t a problem when relaxing is done by a top notch, professional stylist but if you have an amateur, look out!

For more, see this information from the FDA about hair relaxer safety.

Should You Relax?

Despite the safety concerns and extra damage, there are some significant advantages of relaxing over flat iron straightening. These include

  • More permanent
  • Easier to do (if you have a stylist)
  • More consistent results
  • Less prone to negative humidity effects

On the other had, being more permanent might be a negative to some.

The Beauty Brains Bottom line:

Both relaxing and flat ironing damage hair, but relaxing is much worse. However, it does give some added benefits so you might decide hair relaxing is worth extra damage. If you don’t want to lose or damage hair, the best thing you can do is shampoo infrequently, condition each time, and don’t comb or style it much. Of course, that severely limits the type of looks you can get so these aren’t options for most people.

What do YOU think? Would you rather have hair relaxed or do daily flat ironing? Leave a comment below.