Vitamin D

Vitamin D, also called calciferol, is a fat-soluble vitamin obtained through both sunlight and dietary sources. Functionally, Vitamin D acts as a hormone that maintains concentrations of calcium and phosphorus in the blood by enhancing or decreasing absorption of these minerals in the small intestine. Vitamin D also regulates bone metabolism and the deposition of calcium into bones.

Food & Beverage Sources

Vitamin D-rich foods include fatty fish like sardines and salmon, and in the U.S. milk is required to be vitamin-D fortified. Other foods and beverages may also be fortified with vitamin D in the U.S., including ready-to-eat breakfast cereals, milk-based products, soy-based beverages and calcium-fortified juices.

Recommended Intake Levels

The recommendation for vitamin D is 5 micrograms per day for men and women ages 19- 50 (including pregnant and lactating women), 10 micrograms per day for men and women ages 50-70 and 15 micrograms per day for people over 70 years of age.

Although clinical cases of vitamin D deficiency are rare in the U.S, inadequate intakes have recently been found to be much more common than previously thought. A recent analysis of the 1999-2000 National Health and Nutrition Examination Survey (NHANES 1999-2000) found that half of adolescent girls and one-third of 19-50 year-old women did not consume the recommended level of vitamin D intake. The study also showed that use of vitamin D-containing supplements helped to increase the percentage of individuals meeting or exceeding the recommended intake for vitamin D, yet the majority of older individuals still did not obtain enough of the nutrient.

Other researchers who examined the adequacy of vitamin D intake worldwide have concluded that vitamin D intake is often too low in countries without mandatory fortification. Even in countries that do fortify some foods with vitamin D, intakes remain low in some groups because of dietary patterns, such as low milk consumption.

Learn more:

• Straight Facts About Vitamin D (PDF)
• Vitamin D FDA Revised Health Claim
• Vitamin D - Benefits for Bone Health and Beyond: A Conversation with Dr. Michael Holick
• Study Shows Vitamin D2 Is as Effective as Vitamin D3 in Maintaining Circulating Concentrations of 25-Hydroxyvitamin D
• Are you Getting Enough Calcium and Vitamin D?
• Juice Fortification Helps Address Low Vitamin D Intakes
• Vitamin D in the Spotlight: An Expanded Role Emerges for Promoting Health
      (from the International Food Information Council)

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