What Makes Curly Hair Curly?
For many years, it was believed that the shape of a person’s hair was determined by the individual hair shafts, and that curly hair was curly because the cross-section of the hair shaft was flatter and had more intertwined layers than straight hair, which was round. However, more recently, scientists at L’Oreal Paris have found that curly hair and straight hair are determined by the shape of the hair follicle, and that the shape of the hair shaft simply follows suit. It is known that curly hair has a different biological structure than straight hair. It is extremely rare to find someone with hair that is both curly and oily. Biologically, this makes sense, because the oils secreted into the hair shaft by the sebaceous glands can more easily travel down the shaft of straight hair. Anyone with curly hair knows that this hair type can be dry, hard to manage, and often frizzy. The good news is that people with curly hair tend to have fewer split ends than people with straight hair. The amo
The amount of natural curl in a hair depends on the shape of the hair follicles. Straight hair grows from a follicle that is more or less round, and the hair itself is round in cross section. Wavy hair is kidney-shaped in cross section, and the amount of wave in the hair depends on the degree of curve in the follicle. Curly hair grows from a very curved hair follicle. I had to teach this in a high school anatomy class.
john h hersey Answer: Hair is made of protein (just like pretty much everything else in your body). Now in these proteins are sulfur atoms (called sulfides). When two sulfur atoms come together, they form what’s called a disulfide bond. If two sulfur atoms are far apart in the same protein, and they come together to form that bond, the protein is going to bend accordingly. The more disulfide bonds, the curlier the hair. Naturally curly hair has a lot of disulfide bonds. When people with straight hair get a ‘perm’ they are chemically forcing the making of disulfide bonds. These bonds are pretty strong too…very difficult to break. ‘Perm’ is short for ‘permanent wave’ though a ‘perm’ isn’t really permanent. As the new hair grows in, it will be straight and only the ends curly. And it’s very difficult to straighten out naturally curly hair.
