Vitamin D is a fat-soluble vitamin that has many functions in the body. Getting plenty of vitamin D in your diet may help to prevent bone disorders and some types of cancer. Some people are more at risk for becoming deficient in this vitamin than others, putting them at higher risk of osteoporosis and other health problems.
Vitamin D is found in all the cells in your body and helps to regulate calcium and phosphorus absorption, blood-sugar balance and insulin activity, blood pressure, muscle composition and immune system response. It is important in building strong bones, cell differentiation and muscle and nerve function.
If you have vitamin D deficiency, you may experience muscle pain or weakness. Children may get rickets, resulting in bowed limbs and stunted growth, and adults may get osteomalacia, a condition involving soft bones and bone pain, according to the Linus Pauling Institute. A deficiency of vitamin D may also weaken the immune system and cause fatigue, depression and impaired cognitive function.
Eating plenty of foods rich in vitamin D or taking supplements containing vitamin D can help prevent vitamin D deficiency. Food sources include fortified milk, salmon, shrimp, cod, sardines and fortified cereals and juices. Spending a short time in the sun can also provide vitamin D, since your body can synthesize this vitamin with sun exposure. .