What is keratin?
Keratin is a protein that helps form hair, nails and your skin’s outer layer (epidermis). It helps support your skin, heal wounds and keep your nails and hair healthy.
There are 54 kinds of keratin in your body. There are two types:
- Type I: Of the 54 kinds of keratins in your body, 28 of them are type I. Of those, 17 are skin cell (epithelial) keratins, and 11 are hair keratins. Most type I keratins (cytokeratins) consist of acidic, low-weight proteins. They have many functions, including helping protect cells from internal forces in your body (mechanical stress).
- Type II: The other 26 kinds of keratins in your body are type II. Of those, 20 are skin cell keratins, and six are hair keratins. They consist of basic-neutral, high-weight proteins. Their basic-neutral pH helps balance type I keratins and govern cell activity.
There are two forms of keratin:
- Alpha-keratin: Alpha-keratin is in the hair, epidermis, horns and nails of mammals. Type I and type II keratins are alpha-keratins.
- Beta-keratin: Beta-keratin is in the feathers, claws, beaks and scales of birds and reptiles.
What does keratin do to the body?
Keratin provides support and protection in your body. Your hair, nails and skin rely on the amount of keratin in your body for their overall health. Your glands and organs also contain keratin.
Keratin is strong, so it won’t dissolve in diluted acids, alkalines, solvents or waters. Your body has many chemicals in it, and none of them affect keratin. Therefore, many believe that keratin treatments are beneficial for their hair, nails and skin.
Do I need keratin for my hair?
Your body produces keratin naturally.
Animal fur, feathers, hooves and horns also consist of keratin. The keratin in keratin hair treatments usually comes from ground-up animal parts, so if you’re a vegetarian, you may not want to use these products.
Keratin is the primary component of hair, so many people believe that taking keratin supplements makes their hair stronger. However, there are no studies that conclude that keratin supplements make your hair stronger. Talk to your healthcare provider if you’re thinking of taking keratin supplements to discuss any risks and benefits.
Many people also believe that shampoos and conditioners infused with keratin oil make their hair healthier. Studies have shown that shampoos and conditioners that contain keratin hydrolysates can make your hair stronger, brighter and softer.
Getting a keratin hair treatment is a personal decision. It makes your hair shiny and silky while also reducing frizz. However, the treatment is usually expensive, and it may have negative effects on your body.
Keratin hair treatments are chemical protein treatments that make your hair shiny and silky while also reducing frizz. They’re sometimes called Brazilian blowouts.
During a keratin hair treatment, your hairstylist:
- Washes your hair with a special shampoo and then dries your hair with a towel.
- Applies a liquid keratin solution to your hair in small sections.
- Blow dries your hair.
- Runs a flat iron set to a high temperature through your hair. This seals the keratin solution to your hair.
After your hair treatment, you shouldn’t get your hair wet for several days or pull it back with hair clips, scrunchies (elastics), hats or sunglasses. You may have to use special shampoos and other hair products to maintain the treatment.
When performed by a hair care professional, your hair will be smooth and voluminous for up to six months.
Where is keratin located?
Keratin is in your hair, nails and your skin’s outer layer, and it’s also in your glands and organs.
What does keratin look like?
Keratin can exist as alpha-keratins and beta-keratins according to the configuration of its polypeptide chains (the series of amino acids attached by peptide bonds).
Alpha-keratins are mostly fibrous, and their structure looks like the thread of a screw (helical).
Beta-keratins are sheets of polypeptide chains that extend in the same directions and never overlap (parallel). This construction gives beta-keratins their tough, rigid structure.
What color is keratin?
Hair, and the keratin within it, contains a pigment called melanin. Melanocytes are special cells that make melanin. Once made, melanin travels to other cells throughout your body. Melanin provides the pigment in your skin, hair and eyes.
Melanocytes produce two types of melanin that help determine the overall pigmentation that you have:
- Eumelanin: This type of melanin primarily makes dark colors in your hair, skin and eyes.
- Pheomelanin: This type of melanin primarily makes pink or red colors in your body, including lips, nipples, the vagina and the bulbous structure at the end of the penis (glans), as well as hair.
As you get older, the amount of pigment in your hair’s keratin reduces. As a result, your hair turns gray and eventually white.
What is keratin made of?
Keratin isn’t a single substance. It consists of many different proteins, including various types of keratins, keratin-associated proteins (KFAPs) and enzymes drawn from animal tissues.
Conditions and Disorders
Can keratin hair treatments cause hair loss?
Though uncommon, keratin hair treatments can sometimes cause hair damage and loss.
Many keratin hair treatments contain formaldehyde, which is a chemical used as a germicide, fungicide and disinfectant. Funeral homes and medical laboratories also use formaldehyde in dead bodies so they don’t break down as quickly. Long-term exposure to formaldehyde may cause cancer.
In addition to hair damage or hair loss, keratin hair treatments may cause:
What are conditions and disorders that affect keratin?
Some conditions and disorders that affect keratin include:
- Epidermolysis bullosa simplex (EBS). EBS is a disease group in which your skin is delicate and develops blisters easily. Keratin gene mutations are most often the cause of EBS.
- Keratin cysts. Keratin cysts (epidermal inclusion cysts) are a common dome-shaped lump filled with keratin.
- Keratosis pilaris (KP). Keratosis pilaris is a common skin condition where small bumps develop on your arms, legs or butt. An excess of keratin clogs your pores, which causes the bumps.
- Monilethrix. Monilethrix is a rare disorder in which your hair breaks easily. It appears within the first few months of life, and it may also affect your eyebrows, eyelashes and body hair. A gene mutation in type II keratins causes monilethrix.
- Palmoplantar keratoderma (PPK). PPK is a disorder in which the top layer of your epidermis (stratum corneum) on the palms of your hands and soles of your feet becomes very thick. Keratin gene mutations cause PPK.
What are common treatments for keratin conditions?
Certain conditions, like KP, can be treated with over-the-counter moisturizing lotions, medicated creams, gently scrubbing (exfoliating) your skin or laser treatments.
More severe conditions may require:
- A life-long application of urea ointments or other skin-smoothing creams.
- Avoiding environments that worsen side effects.
- Experimental treatments, like gene transfer.
Simple lifestyle tips to help maintain keratin.
Many foods help your body produce keratin. You can help your body boost its production of keratin by eating:
- Sweet potatoes.
A note from Cleveland Clinic
Keratin is a protein that your body produces naturally, and it helps keep your hair, skin and nails healthy and strong. Your body produces keratin naturally, but keratin shampoos and conditioners that contain keratin hydrolysates may strengthen your hair and improve its appearance. Keratin hair treatments can also improve your hair’s appearance and reduce frizz. Talk to your healthcare provider if you experience hair loss, coughing, eye irritation, rashes or other side effects after a keratin hair treatment.
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