Nutritional Deficiencies, Vitamins & Nail Diseases | LearnSkin
Our nails do a lot for us. The fingernails and toenails are considered extensions of the skin that protect the fingers and toes from harm, help us to pick up tiny objects, enhance fine touch, help us when we have a scratch, and improve the visual appearance of the hands and feet. Dermatologists commonly see patients who are displeased with their nail appearance and nail disorders are a common reason for people to go to the doctor.
Nails are aesthetically important to many people and make up a huge portion of the beauty industry in ways to improve their appearance and quality. Nail color, luster, size, shape, thickness, and the health of surrounding skin all add to healthy and beautiful nails. Nail dystrophy, or onychodystrophy, is an umbrella term used to describe abnormal nail changes, including uneven nail ridges, discoloration, texture changes, and overall poor aesthetic appearance. A wide range of factors can lead to an abnormal nail, including genetic nail and skin diseases, cancer and other systemic illnesses, inflammation, infection, and injury.
Nutrition plays an important role in nail health. Deficiencies in dietary intake of vitamins, minerals, and other nutrients can contribute to nail diseases.
Nails and Nutrition
There is scientific evidence that various foods, supplements, and nutrients could improve nail health and appearance. On the other hand, malnutrition and deficiencies in some vitamins and minerals can lead to nail disorders. Here are a few nutrients important for nail health.
Interestingly, too much and too little Vitamin A is associated with nail changes. It is known that too much vitamin A as well as medications that are vitamin A derivatives, such as isotretinoin, can cause brittle nails. Vitamin A toxicity has also been reported to lead to onycholysis (separation of the nail from the nail bed) and nail ridging.
On the other hand, vitamin A deficiency can also cause fragile and easily broken fingernails. Many of the symptoms seen in vitamin A toxicity can also be seen in vitamin A deficiency. In vitamin A deficiency, the nails can become thin and brittle, leading to easy splitting. Vitamin A deficiency is most prevalent in developing countries in malnourished youth and adults, but fat malabsorption and liver disease can also increase the risk for vitamin A deficiency.
Sources of vitamin A
Dietary vitamin A can be obtained from both animal and plant food sources, including fish, milk, broccoli, squash, carrots, kale, and sweet potatoes.
Vitamin B12, also known as cobalamin, is essential for proper metabolism of protein, fat, and carbohydrates. Vitamin B12 deficiency is associated with darkening of the skin and also the fingernails.[6,7] Vitamin B12 deficiency affects up to 15% of people in the world and is most common in the elderly and in strict vegans.
Sources of vitamin B12
In order to get enough vitamin B12 in your diet, aim to increase your intake of dairy, meat, and eggs. If you are vegetarian or vegan, you can also obtain vitamin B12 from fortified cereals and supplements.
Vitamin C is a powerful antioxidant that quenches free radicals and is also an essential factor in collagen production, wound healing, bone health, and iron absorption. Scurvy is the term used to describe the syndrome of vitamin C deficiency and can manifest as easy bruising/bleeding such as bleeding gums, tongue pain, slow wound healing, “corkscrew hairs”, and hyperkeratosis (or thickening of the outermost layer of skin). Low vitamin C shows as bleeding under the nails and a condition called hapalonychia, or “egg shell nails”.
Sources of vitamin C
Vitamin C is abundant in many fruits and vegetables, including oranges, strawberries, bell peppers, broccoli, and dark leafy vegetables like kale.
It is estimated that 2 billion people in both developed and developing countries have iron deficiency. Iron is vital for many functions throughout the body including proper red blood cell formation, protein synthesis, and immune system functioning. Iron deficiency is classically associated with a nail condition called koilonychia, also known as “spoon-shaped nails,” in which the nails become thin and have a spoon-shaped convexity. In addition, iron deficiency can cause the nails to become dry, brittle, and fragile.
Sources of iron
In order to get enough iron in your diet, increase your intake of lentils, spinach, and fortified breakfast cereals.
Selenium is an important trace mineral that is required by antioxidant enzymes throughout the body to neutralize damaging free radicals. White nail discoloration has been reported in patients with selenium deficiency, who also receive IV feedings. The nail changes improved one month after starting selenium supplementation.
Sources of selenium
Brazil nuts, wheat germ, and whole grains are rich in selenium and are delicious healthy foods to include in your regular diet.
Zinc deficiency can result from both genetic diseases and lack of adequate zinc intake from foods. In a rare genetic disease of zinc deficiency, called acrodermatitis enteropathica, patients suffer from multiple symptoms including nail findings of onychodystrophy and skin infections around the nails (called paronychia). Nutritional zinc deficiency is associated with a nail disorder called Lines of Beau, which shows up as grooves across the nails. Lines of Beau can also develop during periods of psychological or physical stress, such as during severe illness.
Sources of zinc
Rich sources of dietary zinc include seafood and fortified cereals.
Adequate dietary intake of vitamins and minerals are important to support proper nail health growth and appearance. Those who are concerned that they might have a nutritional deficiency should seek testing and recommendations from their healthcare provider.
- Rich P, Scher R. Nail anatomy and basic science. An Atlas of Diseases of the Nail. New York: Parthenon Publishing; 2003:7.
- Haneke E. Onychocosmeceuticals. J Cosmet Dermatol.2006;5(1):95-100; PMID: 17173580 Link to Research.
- Jen M, Yan AC. Chapter 130. Cutaneous Changes in Nutritional Disease. In: Goldsmith LA, Katz SI, Gilchrest BA, et al., eds. Fitzpatrick's Dermatology in General Medicine, 8e. New York, NY: The McGraw-Hill Companies; 2012.
- WorldHealthOrganization. Global prevalence of vitamin A deficiency in populations at risk 1995-2005. 2009; Link to Research. Accessed WHO Global Database on Vitamin A Deficiency
- Griffiths C, Barker J, Bleiker T, et al. Rook's Textbook of Dermatology. 9th ed2016.
- Niiyama S, Mukai H. Reversible cutaneous hyperpigmentation and nails with white hair due to vitamin B12 deficiency. Eur J Dermatol.2007;17(6):551-552; PMID: 17951150 Link to Research.
- Jithendriya M, Kumaran S, P IB. Addisonian pigmentation and vitamin B(1)(2) deficiency: a case series and review of the literature. Cutis.2013;92(2):94-99; PMID: 24087784 Link to Research.
- Rajan S, Wallace JI, Beresford SA, et al. Screening for cobalamin deficiency in geriatric outpatients: prevalence and influence of synthetic cobalamin intake. J Am Geriatr Soc.2002;50(4):624-630; PMID: 11982661 Link to Research.
- Chambial S, Dwivedi S, Shukla KK, et al. Vitamin C in disease prevention and cure: an overview. Indian J Clin Biochem.2013;28(4):314-328; PMID: 24426232 Link to Research.
- Hirschmann JV, Raugi GJ. Adult scurvy. J Am Acad Dermatol.1999;41(6):895-906; quiz 907-810; PMID: 10570371 Link to Research.
- Zimmermann MB, Hurrell RF. Nutritional iron deficiency. Lancet.2007;370(9586):511-520; PMID: 17693180 Link to Research.
- Cashman MW, Sloan SB. Nutrition and nail disease. Clin Dermatol.2010;28(4):420-425; PMID: 20620759 Link to Research.
- Sato S. Iron deficiency: structural and microchemical changes in hair, nails, and skin. Semin Dermatol.1991;10(4):313-319; PMID: 1764360 Link to Research.
- Tinggi U. Selenium: its role as antioxidant in human health. Environ Health Prev Med.2008;13(2):102-108; PMID: 19568888 Link to Research.
- Kien CL, Ganther HE. Manifestations of chronic selenium deficiency in a child receiving total parenteral nutrition. Am J Clin Nutr.1983;37(2):319-328; PMID: 6401914 Link to Research.
- Weismann K. Lines of Beau: possible markers of zinc deficiency. Acta Derm Venereol.1977;57(1):88-90; PMID: 74178 Link to Research.
- Lipner SR, Scher RK. Evaluation of nail lines: Color and shape hold clues. Cleve Clin J Med.2016;83(5):385-391; PMID: 27168515 Link to Research.