A hair straightening treatment is a type of cosmetic procedure that is used to remove natural curls and waves from the hair and give it a smooth, straightened appearance. The process generally works by using chemicals that affect the molecules of the hair and breaks down the bonds that give hair strands their waviness or curls. There are a variety of different types of hair straightening treatments that range in effectiveness, cost, and potential damage.
One of the most common types of hair straightening treatments is keratin hair straightening, also commonly referred to as Brazilian hair straightening. Keratin hair straightening involves the use of keratin, a type of protein that occurs naturally in hair follicles. The protein is combined with formaldehyde, a chemical that assists keratin protein in bonding to hair molecules and making them straight. The results of keratin straightening generally remain for approximately two months, after which the treatment will generally need to be reapplied to keep the hair straight.
Thermal reconditioning is another one of the most widely used hair straightening treatments. The treatment is also known as Japanese hair straightening. A chemical solution is applied to the hair and washed, then blow dried and straightened with a flat iron. The exact combination of chemicals used may vary depending on the manufacturer and many of the formulas are patent-protected. They are thought to be effective at straightening by breaking down the hair’s molecular structure so that it keeps the appearance of the hair after it is blow-dried and flat ironed. The effects of thermal reconditioning are typically permanent, meaning the hair’s texture remains straight until new hair grows in.
Chemical relaxers are usually considered one of the more affordable and less damaging types of hair straightening treatments. These types of treatments generally use chemicals that soften and break down the bonds of the hair’s molecules, but in a more gentle and less drastic way than keratin hair straightening or thermal reconditioning treatments. For example, relaxers may make tight curls into smoother waves or soften kinky hair in order to make it easier to manage, but usually does not produce the straight look of other treatments that use harsher chemicals. Relaxing treatments may need to be repeated every two months or so to maintain the texture.
Hair straightening treatments may have certain potentially negative or dangerous consequences. Hair stylists generally warn their clients that the chemicals used to give hair a straight appearance can also damage hair and cause it to become dry or break off, particularly if the hair is also colored treated. These chemicals, especially formaldehyde, may also cause health reactions, including runny nose and eyes, headache, or difficulty breathing, in some individuals.