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Keratins are structural proteins that are found in human hair and fingernails.
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Keratins are structural proteins that are found in human hair and fingernails. A keratin supplement is meant to strengthen your hair while creating shine. Many people obtain keratin treatments from salons and purchase "keratin vitamins" — keratin in supplement form — from drug stores or online.

There are many types of hair and nail supplements on the market today. Biotin is a supplement thought to help produce keratin, thereby strengthening hair and nails, and promoting growth. However, the Mayo Clinic stresses that research showing that keratin supplements work is lacking.

Read more: 9 Things to Do for Amazing Hair

Keratin vs. Biotin

Biotin is a supplement thought to aid in strengthening the keratin protein found in hair and nails, says the U.S. National Library of Medicine. It is also found in foods such as bananas, eggs and milk, in small quantities. Apart from hair loss and brittle nails, it is also used to treat nerve damage, along with a variety of other conditions. The U.S. National Library of Medicine confirms that biotin is deemed effective for treating hair loss resulting from a biotin deficiency.

Biotin deficiency can affect people who are pregnant, malnourished, experiencing rapid weight loss, or who have been tube-feeding for a long time. Cigarette smoking is thought to possibly contribute to low biotin blood levels as well.

Read more: What is a Safe Dosage of Biotin?

An April 2017 review in Skin Appendage Disorders revealed that biotin supplements have not been proven to be effective for strengthening hair and nails in people without a biotin deficiency. Such deficiencies are rare, as biotin is easily obtained in adequate amounts through diet.

Biotin's role in synthesizing protein, particularly keratin, is what makes people think it would be effective for strengthening hair and nails, acting as a indirect keratin supplement. The 2017 Skin Appendage Disorders review stresses that no studies currently available reveal deficiencies of biotin in healthy individuals with balanced diets.

The recommended daily does is only 30 micrograms, and it's available in large amounts in many foods, such as rice, whole grains, egg yolk, liver, salmon, legumes and nuts.

Are Keratin Supplements Dangerous?

The greatest dangers of keratin come from salon treatments that contain formaldehyde. Treatments that are added to hair externally, and then treated with high heat, such as for hair straightening, cause formaldehyde exposure, according to the U.S. Food and Drug Administration.

A potent, odorous gas, formaldehyde is a serious health hazard in these keratin treatments, as outlined by the Occupational Safety and Health Administration. If you are exposed to the gas when the is applied to the hair, it can get into your lungs or eyes. It can then cause breathing problems, like wheezing and coughing, as well as skin rashes and itching. Formaldehyde exposure is also considered a cancer risk.

Read more: The 12 Best Foods for Healthy Hair

As for keratin and biotin oral supplements, the U.S. National Library of Medicine deems them likely be safe. The Mayo Clinic relates that doses of up to 10 milligrams have not been shown to cause any negative effects.

Be aware of taking biotin supplements if you take medications that are changed by the liver, as this supplement might minimize the effects of the medications you are taking. Some examples of these medications would be clozapine, cyclobenzaprine and fluvoxamine. Please speak to your doctor before taking a biotin supplement.


Consult with a doctor before taking any new supplement, especially if you take other medications.

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