Vitamin D, also known as Cholecalciferol is the only vitamin that the human body is capable of producing on its own if it is exposed to sufficient amounts of sunlight. Generally an hour a week is considered enough. All the other vitamins need to be supplied to the body either via a balanced nutritious diet or by consuming vitamin supplements.

The body is able to store adequate amounts of Vitamin D because it is a fat soluble vitamin. It is also a very stable vitamin so it is not broken down if exposed to heat or during preparation.

Sufficient amounts of Cholecalciferol can reduce the risks of Osteoporosis and damage to the joints because of its ability to help the body absorb calcium. This ensures that the bones remain strong and are less prone to being brittle or fractured. It can also delay the effects of arthritis and reduce back pain.

Scientific studies have recently been conducted to prove that Vitamin D can actually protect the body against the risks of developing certain autoimmune diseases and colorectal cancer. The results seem promising so far.

Milk that is fortified with Vitamin D is an excellent source because it has the added benefit of providing the body with calcium too. Foods that are enriched with Omega 3 such as cod liver oil,salmon and tuna are also good. Some other useful sources of Cholecalciferol include organ meats, egg yolks, butter, full-fat dairy products, orange juice and cereals.

It is always recommended that babies that are being breast fed should be giving a Vitamin D supplement. The daily recommended dosage is normally 200 to 400 international units for adults. However, adults aged between 50 and 70 years should get around 600 international units a day.

An important note to keep in mind is that Vitamin D should be consumed in moderation. Over supplementation of this vitamin can lead to the development of kidney stones, over calcification of the teeth and bones and also result in calcium deposits in the arteries that might cause them to harden.

On the other hand, deficiency of Vitamin D can lead to a condition commonly known as 'Rickets'. This disease is especially more common among children. Symptoms include soft or abnormal growth of bones. Infants who are not able to get enough Vitamin D can suffer from soft bones which may later on lead to bow legs, intense pain and stunted growth.

Among older adults, a Vitamin D deficiency can lead to Osteoporosis - A condition where the bones become fragile and are are greater risk of being fractured. As Cholecalciferol is absorbed in the small intestines, diseases of the liver, intestines and gall bladder can hamper the proper absorption and result in a deficiency.