The Importance of Vitamin D

Many Americans may be suffering from unrecognized deficiencies of vitamin D. Most people in the U.S. get vitamin D from food and sun exposure but it is well below the recommended intake, especially during winter.

Vitamin D is a fat soluble vitamin found in food. It can also be made in your body after exposure to ultraviolet rays from the sun. UV rays trigger vitamin D synthesis in the skin. Some important facts about vitamin D:

  • Vitamin D deficient diets are associated with lactose intolerance and strict vegetarianism.
  • Infants fed only breast milk receive insufficient amounts of vitamin D unless they also are given appropriate levels of vitamin D supplementation.
  • Americans age 50 and older are believed to be at increased risk of developing vitamin D deficiency. As people age, skin cannot synthesize vitamin D as efficiently.

Benefits of vitamin D

  • By promoting calcium absorption, vitamin D helps to form and maintain strong bones. A deficiency contributes to osteoporosis.
  • Research suggests that vitamin D may help maintain a healthy immune system. It also regulates cell growth and differentiation.
  • Leg weakness is a common symptom of vitamin D deficiency. According to a report in the Journal of Bone and Mineral Research, vitamin D supplemented women had half as many falls.
  • The Harvard School of Public Health presented evidence that vitamin D appears to have a protective effect against multiple sclerosis (MS).
  • According to a study in the American Journal of Clinical Nutrition, vitamin D may be important for preventing tooth loss. The rate of loss in tooth-gum attachment was 25 percent higher among participants with the least vitamin D.
  • According to research in the Journal of Nutrition, vitamin D signals colon, breast and prostate cells to: differentiate into mature forms, stop growth, and succumb to programmed cell death.
  • In studies involving children and adults with unexplained muscle and bone pain, almost all were found to be vitamin D deficient.

Dietary Intake of vitamin D

  • Recommended: Birth-50 years 200 IU; 51-70 years 400 IU; 71+ years 600 IU.
  • A multivitamin typically has 400 IU.
  • Three ounces of cooked salmon has 425 IU.
  • A glass of fortified milk or orange juice has 100 IU.
  • Three ounces of tuna (canned in oil) has 200 IU.
  • Breakfast cereals may be fortified often at a level of 10-15 percent of the daily value.
  • High caffeine intake may inhibit vitamin D receptors, decreasing bone mineral density.

For more practical information on vitamin and supplements, please go to the Adventist Healthcare website.


Washington Post, Science News, NIH - Office of Dietary Supplements, WebMD and Washington and Shady Grove Adventist Hospitals . The Health Tip of the Week is for educational purposes only. For additional information, consult your physician. Please feel free to copy and distribute this health resource.

Shady Grove Adventist Hospital is located at 9901 Medical Center Drive in Rockville . For more information, go to To find a local physician, call 1-800-642-0101 24 hours a day, 7 days a week.