(Specialist Orthopaedic Surgeon)

Vitamin D

Vitamin D: A gift from the sun.

Vitamin D is one vitamin which is produced in our body by direct exposure to the sun. The vitamin D formed in the skin is processed in our liver and then kidneys to finally form produce the active form of Vitamin D [1,25(OH)2D].

What is the function vitamin D?

Vitamin D plays an important role in absorption of calcium from our food which we eat. It is also needed for bone growth and bone remodeling. Recent studies have shown that it also has role in our neuromuscular and immune function, reduction of inflammation and cell growth.

Research suggests that vitamin D could play a role in the prevention and treatment of a number of different conditions, including type1 and type 2 diabetes, hypertension, glucose intolerance, and multiple sclerosis.

What causes it’s deficiency?

No food items contain adequate vitamin D. Therefore to get sufficient D you need good amount of strong sunlight. Lack of sun exposure is the primary cause of it’s deficiency. Contrary to popular belief early morning sunlight is not sufficient. You need exposure to sun at noon. That’s when the UV rays are strongest.

Other reasons are, insufficient absorption of dietary supplements of vitamin D due to intestinal diseases and failure of kidneys to convert it into active form.However prolonged UV ray exposure has it’s own hazards (including skin cancer). That’s why most doctors rely on supplements rather than prescribing sun exposure.

Effects of vitamin D deficiency:

Vitamin D deficiency in children can cause severe deformities in bone. This disease is known as Rickets. Common presentation of rickets is bow legs. If diagnosed early this condition is reversible by giving adequate vitamin D in diet. As the bone matures the effects become permanent.

In adults the deficiency is known as Osteomalacia. It is characterized by weak bones. In prolonged cases there can be bone pain and muscle fatigue.

Vitamin D deficiency has also been linked with cardiovascular diseases, cancer, autoimmune diseases, infections and some metabolic disorders.


It can be easily diagnosed by blood test estimating 25(OH)D3.


Treatment is aimed at correcting the vitamin D levels in the body. Vitamin D supplements are now available in many forms including tablets, capsules, powder, liquid and injection.

In most patients weekly high dose is given for a few weeks to rebuild vitamin D store quickly. Following which a daily or monthly maintenance dose is recommended.

What will happen if too much vitamin D is taken?

Vitamin D is a fat soluble vitamin and is stored in our body. Unlike some other vitamins very high dose of vitamin D for long period has been associated with significant risk factors. Hypercalcemia and deposition of calcium in kidneys and other tissues can occur.

High dose of vitamin D must always be taken under guidance of a doctor.