Cholecalciferol (Vitamin D3)

A fat-soluble vitamin essential for calcium absorption, bone health, and immune function.

What is Cholecalciferol?

Cholecalciferol, also known as Vitamin D3, is a fat-soluble vitamin produced in the skin when exposed to sunlight.

It plays a critical role in maintaining calcium and phosphorus balance.

History & Background

Vitamin D was discovered during research on rickets, a childhood bone disorder caused by vitamin D deficiency.

Chemical Structure & Properties

• IUPAC name: (3β,5Z,7E)-9,10-secocholesta-5,7,10(19)-trien-3-ol
• Molecular formula: C₂₇H₄₄O
• Molar mass: 384.64 g/mol
• Nature: Secosteroid

Mechanism of Action

Cholecalciferol works by:

• Increasing intestinal absorption of calcium
• Regulating phosphate metabolism
• Supporting bone mineralization

Health Benefits & Uses

• Prevention and treatment of rickets
• Prevention of osteoporosis
• Improves calcium absorption
• Supports immune function

Dosage Guidelines

Adults: 600–800 IU/day

Upper limit: 4000 IU/day

⚠️ Excess intake may cause hypercalcemia.

Vitamin D Deficiency

• Rickets (children)
• Osteomalacia (adults)
• Bone pain
• Muscle weakness

Side Effects

• Nausea
• Vomiting
• Hypercalcemia (overdose)

Frequently Asked Questions

Is vitamin D3 better than D2? – Yes.

Is sunlight a source? – Yes.

Is daily intake needed? – Yes.

Can overdose be harmful? – Yes.

⚠️ Educational content only. Not a substitute for professional medical advice.