Overview
Keratin is a word you might know if you spend much time researching or shopping for hair products. The term has made its way into the names of treatments to make hair smoother, softer, straighter and less frizzy, with companies claiming that the products either contain or act on keratin. But your hair is not the only part of your body in which keratin plays a role. The versatile substance “can be thought of as nature’s all-purpose plastic,” according to Bio-Medicine.org, a site devoted to biology and medicine.
Basics
Keratin is a type of protein–a fibrous protein, to be precise. In various animals, it is present in horns, beaks, claws, hooves, scales and feathers, according to Bio-Medicine.org. It is also part of the skin, hair and nails of humans.
Benefits
Keratin lends a toughness and durability to the various structures in which it is found. Such parts generally function to protect the body from the environment. Keratin gives the skin of humans its waterproof quality, for example. If a certain part of the body, such as hands or feet, experience pressure or rubbing, the number of keratin-containing cells grows to build a callus.
Hair
Keratin explains much about why your hair behaves the way it does. Whether you are having a good hair day or a bad one depends largely on how keratins happen to be bonding. They bond via hydrogen atoms, which can be broken by water, including the moisture in the air. When your hair dries, the bonds reform, fixing the hair in position, according to the Swiss Institute of Bioinformatics. That is why a humid day can wreak havoc on your hairstyle. Blow drying can reorganize the hydrogen bonds and thus facilitates sculpting of the hair.
Types
Alpha-keratin is the type of keratin found in mammals, including humans. Birds and reptiles, on the other hand, have the harder beta-keratin, according to Bio-Medicine.org. In humans specifically, two keratin subtypes are present: the cytokeratins of the epithelium, and the harder hair keratins.
Problems
Keratins relate to some unpleasant conditions in people. The body constantly sheds and regrows keratin-containing cells. When you see white dandruff flakes falling from your scalp, you are actually witnessing the casting off of keratin. And if you find yourself irritated by the itching of athlete’s foot, recognize that it is only your body providing a menu the fungus likes: The fungus that causes the condition feeds on keratin.
