Importance
Vitamin D plays a vital role by assisting in absorption and utilization of phosphorus and calcium in the body. Other important functions include maintaining healthy teeth, bones and helping in the formation of cartilage.
Sources
Vitamin D is available in two forms - D2 and D3. Among these Vitamin D2 can be obtained from foodstuffs such as liver oils, eggs, salmon and mackerel. On the other hand, Vitamin D3 gets manufactured in the body by itself, whenever a person is exposed to sunlight. Apart from this, vitamin D can also be added to other foodstuffs like butter and milk.
Side Effects of Deficiency
Since every person, at some point of time or other during the day, is exposed to sunlight, there are very few cases wherein deficiency of vitamin D is observed. Mostly bedridden people, or people who move out of their homes completely covered are like to report a vitamin D deficiency. Effects of this include – cramps in muscles, marred growth, dental disorders and pain in bones. It can also lead to other diseases like rickets (in children) and osteoporosis (in adults).
Dangers
Dangers of excess vitamin D in the body can be hypercalcamia, cardiovascular damage, weakening of bones or renal damage.

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