Get Started
Get Started
570-558-0290

Health & Exercise Forum

A Little Sun and Vitamin D

, , ,
Apr 8, 2013

Dr. Mackarey's Health & Exercise ForumSpring is here … the days are longer and sun stronger!

This winter I saw local dermatologist, Dr. Ted Stampien, Jr. and his wife, Susan, driving in their convertible. I joked that the only time a dermatologist feels protected from the sun while riding in a convertible is in the winter with the top up. As we discussed the topic of protecting your skin from the sun, he joked that even the most vigilant dermatologists allow for a little fun in the sun. (For the record: he wears a hat and sun block in the summer when the convertible top is down…he emphasizes that there is no such thing as a HEALTHY tan.)

While protection from the sun is very important, Dr. Stampien feels that too much time indoors playing computer games and watching television, can lead to potential problems from lack of exposure to the sun. One must use good judgment and have balance as the potential exists for Vitamin D deficiency due to lack of sun exposure. This problem may be true for individuals who use too much protection or spend most of their day indoors due to occupation or poor health. Therefore, it will be the purpose of this column to discuss the importance of Vitamin D for health and wellness.

Vitamin D, a fat soluble vitamin, is found in food and can be made by your body after exposure to ultraviolet (UV) rays from the sun. The liver and kidney help convert Vitamin D to its active form. Vitamin D assists calcium absorption, which is essential for normal development and in forming and maintaining strong bones and teeth. Without Vitamin D, bones can become thin, brittle and soft. The classic Vitamin D deficiency diseases are rickets in children and osteomalacia in adults. Rickets results in skeletal deformities. Osteomalacia is the softening of bones. Vitamin D is essential for normal bone health and may diminish or prevent the onset of osteoporosis in the elderly.

The requirement for Vitamin D is dependent on age, sex, degree of sun exposure and the amount of pigmentation in the skin. Since Vitamin D can be produced by the body and retained for long periods of time by the body’s tissues, the precise daily requirement has been difficult to determine. Instead, an Adequate Intake (AI) level has been established. AI is a level of intake sufficient to maintain healthy blood levels of an active form of Vitamin D. The AIs are similar for males and females but increase with age:

  • Ages 19-50: 200 International Units (IU)
  • Ages 51-69: 400 IU
  • Age 70 and older: 600 IU

Sources of Vitamin D:

  • Food Sources
    • Fortified foods are a major dietary source of Vitamin D
      • One cup of Vitamin D fortified milk: 98 IU
      • Dairy products (e.g. cheese, yogurt, ice cream) are generally not fortified
      • Orange juice, cereals, pastries, breads, crackers, cereal grain bars may be fortified; read the nutrition label for more information.
    • Only a few foods naturally contain significant amounts of Vitamin D
      • Salmon, cooked, 3 ½ oz: 360 IU
      • Mackerel, cooked, 3 ½ oz: 345 IU
      • Sardines, canned in oil, drained, 3 ½ oz: 270 IU
      • Liver, beef, cooked, 3 ½ oz: 30 IU
      • Egg yolk, one: 25 IU
  • Exposure to sunlight
    • Regular ultraviolet exposure stimulates the skin to produce Vitamin D.
    • Exposure to ultraviolet light or ambient sunlight
    • Exposing the face and hands for 20 minutes, 3 times a week can be sufficient
    • Exposing the hands, legs and arms for 5 to 10 minutes, 2 to 3 times a week, is more than adequate to satisfy requirements.

Vitamin D deficiency can occur when dietary intake of Vitamin D is inadequate, when there is limited sunlight exposure, when the kidney cannot convert Vitamin D to its active form or when Vitamin D is inadequately absorbed from the gastrointestinal tract. Season, geographic location, time of day, cloud cover, air pollution, sunscreens, living indoors and living in cities where tall buildings block adequate sunlight from reaching the ground affect UV ray exposure. Individuals with limited sun exposure are at risk of Vitamin D deficiency. Homebound individuals, people living in northern latitudes (e.g. New England, Alaska), individuals who cover their bodies for religious reasons and people whose occupations prevent exposure to sunlight may need to supplement with Vitamin D. Sunscreens with a sun protection factor of 8 or greater will block UV rays that produce Vitamin D. Older adults have a higher risk for Vitamin D deficiency because the skin’s ability to convert Vitamin D to its active form decreases with age and the kidneys, which help convert Vitamin D to its active form, do not work as well when people age. Individuals with pancreatic enzyme deficiency, Chron’s disease, cystic fibrosis, sprue, liver disease, surgical removal of part or all of the stomach or small bowel disease may need extra Vitamin D because Vitamin D is a fat soluble vitamin and they have reduced ability to absorb dietary fat. Vitamin D supplements are often recommended for exclusively breast-fed infants because human milk may not contain adequate Vitamin D. Consult with your pediatrician on this issue.

Contributor: Janet Caputo, PT, DPT, OCS specializes in orthopedic and neurological rehabilitation as clinic director Mackarey & Mackarey Physical Therapy Consultants, LLC.

Read “Health & Exercise Forum” – Every Monday in the Scranton Times-Tribune.  This article is not intended as a substitute for medical treatment. If you have questions related to your medical condition, please contact your family physician. For further inquires related to this topic email: drpmackarey@msn.com

Paul J. Mackarey PT, DHSc, OCS is a Doctor  in Health Sciences specializing in orthopaedic and sports physical therapy. Dr. Mackarey is in private practice in downtown Scranton and is an associate professor of clinical medicine at The Commonwealth Medical College.

SOURCE: The National Institutes of Health