What Makes Your Hair & Nails Grow?
Keratin is a protein made by cells in your skin that make up your hair and nails. As keratin cells naturally push upward through the skin, they die and then harden, turning into your hair or nails. Known as keratinization, this process is what makes hair and nails grow, and several factors contribute to its sustained momentum. Hair grows an average of 3 inches a year, whereas nails usually grow about 1 1/2 inches a year.
Significance
A doctor can tell a lot about a person’s overall health simply by looking at hair and nails. A healthy body will produce strong and smooth nails, whereas a diseased body will create dry, brittle, dotted, yellow, pink or otherwise irregular nails. A well-functioning kidney and thyroid, as well as balanced hormones, are especially essential for the healthy development of hair and nails.
Types
Minerals for Fingernails and Fine Hair
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Several types of nutrients support nail and hair growth 1. When you ingest protein in foods such as animal meat or leafy green vegetables, your body breaks it down into amino acids, then redistributes it as needed to build new proteins specific to its needs. Because the production of keratin depends on this process, proteins are essential for nail growth.
In addition, some of the amino acids necessary to produce keratin rely on having a sufficient amount of sulfur in the body. Vitamin A helps your body absorb protein correctly and is known to aid in the physical composition of hair and nails. Vitamin C works with zinc to create collagen, which helps develop healthy connective tissue to support other structures in your fingers and the rest of your body. Vitamin B2 helps develop new tissue, and Vitamin B7, also known as biotin, helps develop stronger, smoother nails. Vitamin E, Vitamin D, iron, calcium and iodine also aid in the healthy development of hair and nails.
Getting needed nutrients to your fingers and scalp through good blood flow is also necessary for your hair and nails to grow. Poor circulation generally results in thin, weak nails and brittle, stringy hair.
- Several types of nutrients support nail and hair growth 1.
- In addition, some of the amino acids necessary to produce keratin rely on having a sufficient amount of sulfur in the body.
Considerations
Because your hormones fluctuate at different stages of life and your body may change with age, your hair and nail quality and growth rate may decrease with age. Seasonal changes also affect growth; your nails and hair grow faster and stronger when they get plenty of Vitamin D and stay moist. Thus, during summer months, they grow more than in cold and dry winter months.
Misconceptions
Will Vitamin B Complex Harden Fingernails?
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You may have heard that hair and nails continue growing after you die. This common misconception is created by an optical illusion. Bodies become increasingly dry and dehydrated after death, causing the skin covering the scalp and skeleton to shrink, which makes the hair and nails appear longer.
Healthy Nails
A healthy, normal nail is smooth, without ridges or grooves. These features can be normal variants, but ideally, all the nails are uniform in color and consistency and free of spots or discoloration.
Related Articles
References
- Journal of Investigative Dermatology: Human Hair Keratins
- “Formation and Structure of Human Hair”; P. Jollès, H. Zahn, H. Höcker; 1997
- Yale School of Medicine: Hair
- Singal A, Arora R. Nail as a window of systemic diseases. Indian Dermatol Online J. 2015;6(2):67-74. doi:10.4103/2229-5178.153002
- Yaemsiri S, Hou N, Slining MM, He K. Growth rate of human fingernails and toenails in healthy American young adults. J Eur Acad Dermatol Venereol. 2010;24(4):420-3. doi:10.1111/j.1468-3083.2009.03426.x
- Schons KR, Knob CF, Murussi N, Beber AA, Neumaier W, Monticielo OA. Nail psoriasis: a review of the literature. An Bras Dermatol. 2014;89(2):312-7. doi:10.1590/abd1806-4841.20142633
- Abdullah L, Abbas O. Common nail changes and disorders in older people: Diagnosis and management. Can Fam Physician. 2011;57(2):173-81.
- Sarkar M, Mahesh DM, Madabhavi I. Digital clubbing. Lung India. 2012;29(4):354-62. doi:10.4103/0970-2113.102824
- Haneke E. Controversies in the treatment of ingrown nails. Dermatol Res Pract. 2012;2012:783924. doi:10.1155/2012/783924
- Jefferson J, Rich P. Melanonychia. Dermatol Res Pract. 2012;2012:952186. doi:10.1155/2012/952186
- Aging Changes in Hair and Nails. Medline. National Institutes of Health Public Information Sheet.
- Nails and Nail Problems. American Academy of Dermatology Public Information Sheet.
Writer Bio
Based in San Diego, California, Jill Blessing has been writing since 1997. Her work has been published in "Triathlete" magazine, "CMYK" magazine, "Kansas City Homes & Gardens" magazine and "The Columbia Missourian." She holds a bachelor's degree in journalism from the University of Missouri.