No better example can be there in the recent history of medical science for the “paradigm shift” in our understanding than witnessed by Vitamin D. Vitamin D depicts the unique transformation of our conventional understanding to the current & modern knowledge recognizing its diversified role traversing the boundaries of different fields of medicine. For nearly more than a century vitamin D has seen the expanding interest of variety of medical specialty ranging primarily from endocrinologists, nutritionists, orthopaedicians, paediatricians now to more diverse groups like oncologists, cardiologists, rheumatologists, immunologists etc. The growing interest of the medical experts is due to the ever increasing publications emphasizing the role of vitamin D in variety of clinical conditions.

Vitamin D has been conventionally known as “anti-ricketic factor” or “sunshine vitamin”. It has also been referred to as unique “vitamin-hormone” because it is a vitamin synthesized by the body and functions as a hormone.1 Besides its conventionally established role in calcium homeostasis and bone mineral metabolism, vitamin D endocrine system in now recognized as a steroid hormone that regulates an extremely complex system of genomic functions that are relevant to such diverse and fundamental bio-activities as cell differentiation, inhibition of cell growth, immune regulation, immune modulation and prevention of neoplastic transformation.2-9 Recent evidences link vitamin D endocrine system with diseases like hypertension, myopatic disorders, and susceptibility to infection, autoimmune disorders and cancer.4,10-14

Despite of such an overwhelming role, it has been the most underrated nutrient. All Indian studies consistently point to low vitamin D levels in the populations studies despite abundant sunshine. The vitamin D status of children has been found to be very low in both urban and rural population studied. Pregnant women and their new born had low vitamin D status as seen in various studies. All studies have uniformly documented low dietary calcium intake compared to Recommended Daily/Dietary Allowances (RDA) by Indian Council of Medical Research (ICMR).15

In the advent of the new understanding emerging for the role of vitamin D and in the context of the evidences pointing towards a paradox of uniform low levels of vitamin D in variety of our population despite of being blessed with plenty of sunshine, warrants a need to revisit the role of this “vitamin-hormone” for the benefit of our ailing masses.