Vitamin D is a fat-soluble vitamin like A and E. This vitamin is hard to obtain from food. Luckily, sunshine is a significant source of this vitamin because UV rays from the sun trigger Vitamin D synthesis in the skin.

Vitamin D is tasked with the crucial role of maintaining normal blood levels of calcium and phosphorus. By promoting calcium absorption, the vitamin helps to form and maintain strong bones. It also has to work efficiently with other vitamins, minerals, and hormones in order to promote bone mineralization.

Because it acts as an overall guardian of the human skeletal system, Vitamin D helps maintain a healthy immune system and regulate cellular growth and activity.

Vitamin D Sources

One cup of Vitamin D fortified milk supplies one-half of the recommended daily intakes for adults between the ages of 19 and 50 and one-fourth for adults between the ages of 51 and 70.

Although milk is typically fortified with Vitamin D, this is not the case with dairy products made from milk, such as cheese and ice creams. Some ready-to-eat breakfast cereals, though, may be fortified with the vitamin.

Unfortunately, there are only a few commonly consumed foods that are good sources of the vitamin and these are cod liver oil, salmon, mackerel, tuna fish, sardines, margarine, egg, liver, and beef.

The classic Vitamin D deficiency diseases are rickets among the young and osteomalacia among adults. Deficiency in this vitamin indirectly causes osteoporosis since the vitamin is required to promote calcium absorption in the body.

Lorna Mclaren has more information regarding vitamins at http://www.123-nutrition.com. There are informative articles regarding Herbal Alternatives and Health Food Supplements.