Dense, tightly curled hair can seem invulnerable, because it resists combing and may be difficult to straighten. It can be tempting to treat your hair harshly if it's thick, tightly curled or coarse. But each twist of a curl is a weak spot, which means that your hair is more fragile than it seems. African-American hair becomes even more fragile when processed with strong chemicals or styled with heat. To keep African-American hair healthy and manageable, gentle handling will yield much better results than trying to process your hair into submission.