Vitamin D3.

 

Vitamin D is also known as the ‘sunshine vitamin’. Our body produces this vitamin through exposure to sunshine. Vitamin D helps in the absorption of calcium and phosphorous and is thus essential for bone formation and for healthy teeth. In humans, vitamin D is unique because it can be ingested as Cholecalciferol (Vitamin D3) or Ergocalciferol (Vitamin D2) and because the body can also synthesize it (from cholesterol) when sun exposure is adequate hence its nickname, the “sunshine vitamin”.

Vitamin D3 is both a vitamin and a hormone. It acts as a vitamin when it binds with calcium for proper absorption. Humans cannot digest calcium without adequate amounts of Vitamin D3. The most common reasons for Vitamin D3 deficiency relates to the lack of exposure to sunlight and infrequent consumption of vitamin D rich food.


Function


Vitamin D helps the body to absorb calcium. Calcium and phosphate are two minerals that are essential for normal bone formation. Throughout childhood, your body uses these minerals to produce bones. If you do not get enough calcium, or if your body does not absorb enough calcium from your diet, bone production and bone tissues may suffer. Its deficiency causes decalcification of bones which in turn can cause rickets in children and Osteomalacia in adults.


Sources


The body makes Vitamin D when the skin is directly exposed to the sun. That is why it is often called the “sunshine” vitamin. Very few foods naturally contain Vitamin D. As a result, many foods are fortified with vitamin D. Fortified means that vitamins have been added to the food. Vitamin D is found in the following foods:

• Dairy products like cheese, butter, cream and fortified milk.

• Fortified breakfast cereals, margarine, and soy milk.


It can be very hard to get enough Vitamin D from food sources alone. As a result, some people may need to take a vitamin D supplement. Vitamin D found in supplements and fortified foods come in two different forms:

• D (Ergocalciferol)

• D (Cholecalciferol)


The Three Forms of Vitamin D3:

• Cholecalciferol: The unhydroxylated form of Vitamin D3. This is the form in which the nutrient exists when it is absorbed or ingested.

• Calcifediol: Also known as calcidiol, hydroxycholecalciferol, or 25-hydroxyvitamin D3, and is abbreviated 25OH-D.

• Calcitriol: Also referred to as 1, 25-dihydroxy vitamin D3, this is the active form of D3. This form of the nutrient is attained only following 3 two separate chemical reactions designed to process the nutrient for use by the body.


Deficiency


Vitamin D3 Deficiency is a condition in which the blood levels of Vitamin D3 are chronically low for an extended period of time. People who live in cold, northern, mountainous regions and those with darker-than average skin are among the most at risk, although anyone can become deficient if sufficient sunlight is not absorbed and if the individual is not obtaining enough of the nutrient through foods and supplements. Vitamin D3 Deficiency has been linked to increased susceptibility to developing roughly 2-1/2 dozen diseases and illness including everything from Cancer to Osteoporosis, Rickets and Parkinson’s disease.


Treatment


A daily dose of 25-125 µg (1000-500 IU) of Vitamin D cures rickets and Osteomalacia. Because of the risk of toxicity, this should be reduced to 10 µg, the prophylactic dose, when plasma alkaline phosphatase has returned to normal and radiographs show that healing is established. An adequate intake of calcium is essential. The best source is skimmed milk and exposure to sunlight for ½ an hour.


Dr Jyotika arora 

Consultant pathologists