I get this question a lot from my patients and I think it is a question black women struggle with on a regular basis. Let’s start with the basics: The hair shaft is made up of an outer portion, called the cuticle, and an inner portion, called the cortex. The cuticle layer protects the inner layer and is what you see when your hair looks dull or shiny. The cortex is the part of your hair that is responsible for the strength of your hair. Both become damaged from routine styling.
Relaxers contain very alkaline solutions (sometimes as high as a pH of 13-14) that break up the strong bonds in the cortex, called disulfide bonds, so that the hair can be permanently straightened. Obviously, when the strong bonds are broken, the hair shaft becomes weaker and can be prone to breakage if not taken care of properly. Additionally, scalp burns and hair loss from relaxer applications are not uncommon and can occur at any time. For this reason and many others, it is important to have a stylist apply relaxers to avoid over-processing the hair.
Flat irons and other heating tools temporarily break weak bonds in the cortex, called hydrogen bonds, that are easily formed when water is applied to the hair. However, the damage from thermal styling is cumulative, which means the amount of damage increases each time high heat is applied to the hair. Unlike relaxers, which are reapplied to virgin, unprocessed hair, the entire hair shaft must be subjected to damage each time the hair is straightened.
So which I do recommend? There’s no one right answer for everybody so while I encourage caution with any straightening process, I generally recommend relaxers for women who wish to wear their hair in a straightened style more than 50% of the time. This is because the damage is a one-time insult and as long as relaxer is not applied to previously treated hair, the damage does not accumulate over time. However, women with relaxed hair should avoid using thermal styling tools as this would worsen damage to the hair. I also recommend regular protein treatments and deep conditioners to protect the hair.
For women who are comfortable wearing their hair in a curly state for most of the time, thermal styling should be limited to a few times a year. This should be done on the lowest heat setting possible and with a heat protectant. Heat protectants minimize the amount of heat directed towards the hair shaft but it does not eliminate damage. Regular protein treatments and deep conditioning are also important in this case.
By Dr. Crystal Aguh
Dr. Crystal Aguh is an Assistant Professor of Dermatology at Johns Hopkins Hospital in Baltimore, MD. You can find her on Instagram at CrystalADermDoc