Vitamin D: recent advances, associated factors, and its role in combating non-communicable diseases.

The field of nutrigenomics has produced numerous studies indicating the impact of vitamin D on various disease conditions. Trace elements of this vitamin in the body play a significant role in the regulation of body metabolism. This immunomodulatory vitamin plays a role in management of both communicable (viz. respiratory illness like COVID-19 and Respiratory tract infections) and non-communicable diseases e.g., cancer, osteomalacia, diabetes, and cardiovascular diseases. Deficient levels, i.e., vitamin D deficiency in body can lead to the onset of chronic non-communicable illnesses. Vitamin D plays a direct and sometimes indirect role in the progression (when deficient) and prevention (when sufficient) of non-communicable diseases. This essential nutrient may be obtained through dietary intake or supplements. However, the absorption of it relies on various factors, including the presence of complementary nutrients, chemical forms, and external stimuli such as UV-B and a healthy gastrointestinal tract. This review discusses vitamin D absorption and its role in non-communicable diseases with updates on methods for evaluating and fortifying this vitamin in varied diets. We also briefly highlight recommended dietary allowances by age group, absorption difficulties, and its significance in non-communicable disorders.