Adults between 19 and 70 years old -- including pregnant and nursing mothers -- need approximately 600 international units of vitamin D each day. People 71 years old and over should have at least 800 IU daily. However, the Centers for Disease Control and Prevention reports that more Americans are deficient in vitamin D than iron, vitamin C or vitamin B-12. Inadequate vitamin D may contribute to a variety of health problems, including peeling nails. Talk to your doctor if you're concerned about your vitamin D intake.
Effect of Vitamin D Deficiency
According to Toronto-based family medicine practitioner Dr. Sheila Wijayasinghe, nutritional deficiencies are one of the four main causes of nail problems like peeling or cracking. A lack of fat-soluble vitamins like vitamin D or A is a primary reason. Not only does vitamin D itself appear to play a role in maintaining nail integrity, the nutrient is necessary for proper calcium absorption and to regulate the concentration of the mineral in your blood. Calcium is also required for nail health; peeling nails may indicate that low vitamin D is affecting your calcium level.
Who's Most at Risk
African-Americans, people who live in latitudes where there is little sunlight during certain parts of the year and individuals who keep most of their skin covered when they're outside for climate or religious reasons are more likely to develop a vitamin D deficiency that can result in peeling nails. That's because much of the vitamin D in your body is synthesized in your skin when you're exposed to the sun's ultraviolet rays. Being obese or elderly also increases your risk of vitamin D deficiency, as does having a diet that limits animal products, such as a vegan, strict vegetarian or macrobiotic diet.
How to Get More Vitamin D
To increase the concentration of vitamin D in your body -- and possibly help treat or prevent peeling nails -- include plenty of vitamin D-rich foods in your diet. Fatty fish like salmon are some of the best natural sources. A 3-ounce serving of swordfish contains 566 IU of vitamin D, nearly 100 percent of the recommended daily intake for most adults. Salmon supplies 447 IU in every 3 ounces. Vitamin D-fortified foods, many of which are vegan-friendly, are another good source, including plant milks, regular yogurt or milk, breakfast cereals and orange juice. Sun exposure for five to 30 minutes at least twice a week will also help raise your vitamin D level; always wear sunscreen to avoid skin damage.
Other Causes of Peeling Nails
Vitamin D deficiency isn't the only thing that can cause peeling nails. The condition may simply be caused by overexposure to cleaning chemicals or water from dishwashing or swimming. It may also be caused by medications that interfere with vitamin D absorption, such as phenobarbital or isoniazid, or underlying medical problems like an underactive parathyroid gland, liver or kidney problems or a fungal infection. Don't attempt to self-treat peeling nails through vitamin D alone without checking with your doctor, especially if you are experiencing any other type of symptom. In addition, you can lack vitamin D without having nail or any other problems. The only way to be sure is to have your blood level tested.
- Linus Pauling Institute: Vitamin D
- Centers for Disease Control and Prevention: Second National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population 2012 -- Executive Summary
- The Globe and Mail: Why Do My Fingernails Peel and Crack?
- Daily Nutrition Review: Why Do Nails Split, Crack or Peel? -- Possible Nutritional Causes
- NYU Langone Medical Center: Vitamin D Deficiency
- Office of Dietary Supplements: Vitamin D