What really causes bad hair? In short, all roads lead back to damage. Damaged hair happens as a result of a combination of mistreatment over time. The cuticle goes through weathering—the gradual wearing away of the cuticle of the hair shaft. This exposes the cortex, which slowly degrades. Visible damage, including hair breakage, eventually occurs.

Another telltale sign of damaged hair is split ends. The classic split end starts when large areas of the cuticle have split away, showing the cortex underneath. A crack begins to run back up the hair shaft, and if the problem is really severe, the cortex bursts right out of the damaged hair.

While those are some of the symptoms of damaged hair, there are different kinds of damage. Let’s look at the biggest culprits.

Chemically Damaged Hair

Hair color perms and relaxing are wonderful things in that they let us change our look and hairstyle. But all of these processes cause damaged hair, as well

Perms and relaxers, two things which can cause damaged hair, change the shape of the hair via the agents in them that first break the disulphide bonds in hair. The hair is then formed into its new shape and neutralized. This is the term given to the re-shaping of the chemical bonds in their new positions—the process that fixes the hair permanently into its new shape.

Hair color, which can also cause damaged hair, changes hair by penetrating the cuticle to enter the cortex, which damages the F-layer.

Damaged Hair from the Sun

Sunshine is essential for life, but it can zap the life right out of your hair. The ultraviolet light in direct sunlight affects the cuticle in a similar way to bleach, eventually breaking down the keratin protein in the hair. This can result in light streaks and dryness in damaged hair. This is especially troublesome for  color treated hair, which can be compromised. If you’re going to spend time at the beach or be in the sun for an extended time, a hat is a great (and fashionable) way to protect your hair.

Damaged Hair: Everyday Wear and Tear

Hair is by nature fairly robust and can withstand a lot of styling abuse, but it can still be damaged by over-zealous brushing and combing, especially if it's wet and/or tangled. Metal combs are a major watch out as is backcombing (careful when creating your bouffants, ladies), as it tugs against the scales of the cuticle and can cause damaged hair. Once hair has been backcombed the delicate scales of the cuticle are lifted, and the next time a comb passes over these scales they may be ripped off.

Heat is an obvious source of damaged hair’s dryness and unmanageability. It really robs hair of the moisture that is crucial to its lush feel. In fact, if a heat appliance is too hot, it can actually cause the water in the hair to boil and for bubbles of heat to form inside the softened hair shaft! This, too, is a source of damaged hair. Minimizing the use of heat on your hair and setting your heated styling tools at the lowest possible temperature will work like a charm to help keep your hair soft and healthy looking.

Damage Control!

It's much easier to treat hair before it's damaged, versus treating damaged hair. Unfortunately once the cuticle is significantly damaged its structure cannot be 100% repaired. This is a case where an ounce of prevention is worth a pound of cure, and your best weapon is conditioner. The internal structure of hair is dependent on strong sulfur bonds and weaker hydrogen bonds. Without sufficient moisture, the number of hydrogen bonds may be reduced. Conditioning allows re-establishment of the hydrogen bonds and improves the moisture content of damaged hair by improving the weatherproofing of the cuticle.

The star ingredient in Pantene conditioners is a special positively-charged dimethicone, a silicone compound that selectively deposits onto the damaged hair sites. Dimethicone also protects the hair from damage by reducing its resistance to brushing, combing and styling while it’s wet as well as dry.

Other conditioner ingredients that also work well to smooth the outer layers of the cuticle include fatty alcohols, which are also known to penetrate and help moisturize damaged hair.

Having an in-depth knowledge of what causes damaged hair is the first step in getting and keeping your most beautiful hair, and this list is a good crib sheet of the biggest offenders:

  • Not understanding your own hair and choosing the wrong hair care and styling products. Get to know your hair and work with it to help avoid damaged hair.
  • Lightening the color of your hair more than it can tolerate can cause damaged hair. The general rule of thumb is that you shouldn’t alter your hair color more than two shades lighter or two shades darker than what you were born with.
  • Continually trying to correct previous mistakes. We’ve all had some hair disasters, but sometimes it’s best to suffer a bit and let your damaged hair recover and grow-out from whatever mistake you made, whether a cut or color or both, instead of getting it cut again or “fixing” the color, which can cause damaged hair. A little patience will save you both time and money in the long run.
  • Not conditioning frequently. You really do need should to condition every time you wash your hair