When naturals straighten their hair, it's common to use heated tools. So, naturals must protect hair from heat damage because it is a major culprit in breakage
and curl retardation.
The truth is heat free natural hair tends to thrive better than hair that is exposed to heat on a repeated basis. One of the first rules of natural hair is to limit the use of heated tools on your hair. Heat, depending on the intensity and frequency with which applied, can cause the bonds of the hair to break temporarily or sometimes permanently. In the latter case, the actual structural curl pattern of the hair changes, resulting in looser, less defined curls or sometimes bone straight hair.
Heat abstinence is a fundamental, foundational principle that should be adopted very early in any natural hair journey. If you frequently apply heat to your hair, although it will offer instant physical benefits, over time your hair will suffer if you don't take measures to protect hair from heat damage. Think long term when dealing with your hair, especially if length retention is among your hair goals.
There are a few ways you can protect your hair from heat damage.
1. Low Heat Setting: Some hair irons can be dialed to a variety of heat settings, from 175 or so to nearly 400. The 400-degree setting is "definitely too high" for personal use. Choose dryers with a nozzle attachment to target air flow and a diffuser to help distribute heat more evenly.
2. Moisturize Hair: Moisturized or protein-rich hair can withstand high heat better than dry brittle hair.
3. Heat Protectant: A heat protectant serum should be applied to your hair every time a heated tool comes near it. Silicone-based products, specifically, provide glide for the tool and also absorbs a lot of the heat themselves. Grapeseed oil, because of its high burn point, can also be used as a heat protectant.
4. Refrain from Ironing Damp Hair: A hot flat iron should never be applied to damp hair. Your natural strands are more fragile when wet.