Vitamin D deficiency in India
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6060930/

Prevalence of Vitamin D deficiency ranged from 40% to 99%

Most of the studies reporting a prevalence of 80%–90%

Prevalent in all the age groups and high-risk groups alike

Factors

Major source, synthesis in skin on exposure to sunlight

Ultraviolet B (UV-B) radiation, wavelength 290–320 nm

Fish, fortified food, supplements

Vegetables and grains are poor sources

Latitude, solar zenith angle, atmospheric pollution, ozone layer, and melanin pigmentation

Defining levels

Threshold levels of serum 25(OH) D required to optimize effects may vary in the various target organs

Deficiency, less than 20 ng/ml  (50 nmol/L)

Insufficiency, 21 – 29 ng/ml (52 - 72 nmol/L)

Sufficiency, more than 30 ng/ml (75 nmol/L)

Toxicity, more than 150 ng/ml (375 nmol/L)

Desirable and safe range of serum 25(OH) D level would be 30–100 ng/mL (75 – 250 nmol/L)

Metabolism

Vitamin D is needed to facilitate calcium absorption from the gut

PTH is secreted in response to low blood serum calcium

Maintains serum calcium by moving calcium from bones to blood

At less than 20 ng/mL of serum 25(OH) D, PTH is elevated to maintain serum calcium from bony reserves

At serum 25(OH) D levels of intestinal calcium absorption reaches its peak, 

and PTH levels continue to fall up to levels 30 ng/mL

Consequences of Vitamin D deficiency

Rickets

Muscle strength reduction

Autoimmune diseases

Cardiovascular diseases

Depression

Suicide

Parkinson’s

Cancer

Infections

Tuberculosis

Obesity

Diabetes mellitus type 2

Important for:

Immune function

Inflammation

Cell proliferation and differentiation

What to do

Create awareness among the public and healthcare providers about the importance of Vitamin D

and the consequences of deficiency

Indian diet generally fails to satisfy the daily requirement of Vitamin D for a normal adult

Need for fortifying various foods with Vitamin D, through national programs

This silent epidemic should be addressed appropriately with concrete public health action.

we can imagine the burden, this silent epidemic would cause the development of the country.