Heat should be used with care on hair but especially black hair, as the hair is prone to be dry anyway. Heat from styling equipment such as curling irons, hooded dryers, pressing combs, and blow dryers are very damaging to our hair. If smoke can be seen coming from the barrel of a hot comb or curling iron then the appliance is too hot and will cause hair breakage. The lowest possible heat should be used on any appliance and a heat protectant should be placed on the hair before applying heat.
Heat works by breaking the hydrogen bonds in the hair, this is why hair will curl around the barrel of a curling iron or straighten with a pressing comb or flat iron. After the bonds are broken the cool air in the atmosphere will allow the hair to be set in the shape that was created. Women with processed hair are especially prone to over-processing their hair when they use heat. The hair’s protein bonds are already broken down and when the hair is further broken down it is more susceptible to breakage. Natural hair ladies are also at risk especially if they straighten their hair all the time. Straightening hair is still a process albeit one that can revert quickly but it allows for some breaking down of the hair’s structure.
Here are three tips to prevent heat damage to your precious tresses:
1. Using natural heat from your body to steam hair is far better than sitting under a hooded dryer or to blow dry hair. This process will take longer but it works just as well. If your hair is contained under a non-porous surface such as plastic it traps the heat to your head. The added benefit of not going under the dryer is that your hair bond is not broken down. Too much hot air will blow the hair cuticles so far open that even the best conditioners will fail to make a difference. If this application of heat happens on a regular basis then the cuticle layers will get damaged over and over again and the hair will lose its tensile strength and will break.
2. Use a heat protectant. Heat protectants prevent the breakdown of the proteins in hair, they prevent the hair cuticles from cracking, and prevent the hair from losing water in the hair strand and they allow the hair to maintain its strength after a heat treatment. Using heat that is too high though, can and will negate the effects of a protectant. The best rule of thumb is to use the lowest heat setting on your heat appliances when styling or drying hair.
3. Never use heat appliances on wet (dripping wet) hair . Towel dry or give your hair a chance to air-dry before you head under a dryer with medium or even low heat, or attempt to flat iron hair.
Why? Because using heat when the hair is wet can create what is known as the bubble effect. This means that the excess water on hair practically boils on your hair shaft when direct heat is applied, this causes the dreaded “bubble hair” effect. In essence what this means is that the heat causes the water particles on the wet hair to literally boil and steam, causing the hair cuticle to burst and leaves the hair with a sponge-like consistency. This leads to knots on the hair and this can eventually lead to hair breakage or cause split ends, and even alopecia.
Source: Persadsingh Neil, The Hair in Black Women, XulonPress.com, 2003.