Vitamin D also known as the "sunshine vitamin," is produced in the skin upon sun exposure. Vitamin D is also obtained through the dietary consumption of foods such as fish, eggs, mushrooms, milk, fortified foods, etc. Vitamin D is required to maintain serum calcium homeostasis and, for bone metabolism [2].

Vitamin D deficiency is a global health issue that afflicts about 1 billion people worldwide, while 50% of the population has vitamin D insufficiency. Vitamin D deficiency may be related to populations who have limited sun exposure due to geographical location, higher skin melanin content. 80% of adults in India are Vitamin D deficient. 96% of the elderly population in India is Vitamin D deficient [1].

Inadequate exposure to sunlight is one of the major causes of vitamin D insufficiency or deficiency. Vitamin D deficiency can also result from several other causes like decreased dietary intake and or absorption, decreased endogenous synthesis, and increased catabolic metabolism.

Sufficient vitamin D is required for optimal health. It is a versatile vitamin with multiple action. Several studies have shown positive and potential effects of Vitamin D3 on several bone diseases, muscle weakness, more than a dozen types of internal cancers, multiple sclerosis, and type 1 diabetes mellitus.

References:

1. Sizar O, Khare S, Goyal A, et al. Vitamin D Deficiency. [Updated 2022 Jul 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK532266/

2. Chauhan K, Shahrokhi M, Huecker MR. Vitamin D. [Updated 2022 Sep 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441912/