Among all the vitamins, the only vitamin that is not taken with our meal is vitamin D. Rather it’s been formed in the skin with the help of sunlight. You will see lots of commercials about how to prevent and save yourself from sunlight and there you also see many dangers of being under sun. But in fact for enough production of vitamin D, the sun exposure duration required is minimum. It is true that too much exposure to sun light is harmful for us due ultraviolet rays. But the exposure duration required for adequate vitamin D production is very little. A few minutes a day is sufficient.

Vitamin D performs a very important function for our body. It controls the amount of Calcium that is absorbed into our body from food through gut. This calcium is needed for building strong teeth, bones and also needed for our skeletal muscles to contract as well as cardiac muscles. Nerve conduction is impaired without calcium. It’s a very important component of our blood coagulation system. Without this our coagulation system won’t work properly. So calcium is very important for us and its concentration in the blood should remain at a certain minimum level to perform all these mentioned tasks properly and Vitamin D ensures it.

Now what is basic mechanism by which the vitamin D is formed in our body? The inactive form of vitamin D is 7-dehydrocholesterol. This is converted to Vitamin D3 by ultraviolet ray. Another name for the vitamin D3 is cholecalciferol. This form is then converted to an active form in the liver by hydroxylation and named as 25-hydroxycholecalciferol. Finally this 25(OH)D3 is converted to more and final active form by another hydroxylation process in the kidney and the active form named as 1,25-dihydroxycholecalciferol. This active form is produced with specific signals in response to needs of the body. It regulates the absorption in the intestine; regulates the absorption or secretion of calcium from bones and regulates the re-absorption in the liver and kidney.

Dark skinned people, sun light deficient people needs dietary supplement. Cod liver oil, oily fishes, beef liver, a whole egg are the good dietary sources of vitamin D. A regular exposure to sunlight otherwise will sufficient to produce necessary amount of vitamin D.

The deficiency of vitamin D will cause rickets, osteomalacia, osteoporosis. Rickets is a childhood disorder of this vitamin deficiency characterized by long bone deformity with growth retardation. Osteomalacia is a disorder of adult characterized by bone thinning, proximal muscle weakness. Osteoporosis is characterized by reduced bone mineral density and increased bone fragility.

So ensure adequate sunlight exposure daily, and if can’t ensure this you should have vitamin D supplement. Sunlight exposure is needed for all age group. Too much of anything is bad which is true for sunlight also. Thus don’t just avoid sunlight. Love it and live healthy life.