D3 (Cholecalciferol)

Definition

Cholecalciferol, also known as Vitamin D3, is a fat-soluble vitamin that plays a critical role in calcium and phosphorus metabolism. It is produced in the skin upon exposure to sunlight and can also be obtained through dietary sources or supplements.

5 Must Know Facts For Your Next Test

1. D3 is essential for the absorption of calcium in the intestines.
2. It helps maintain normal blood levels of calcium and phosphorus.
3. Vitamin D3 deficiency can lead to conditions such as rickets in children and osteomalacia in adults.
4. D3 is metabolized in the liver to 25-hydroxyvitamin D, which is then converted to its active form, calcitriol, in the kidneys.
5. Excessive intake of Vitamin D3 can result in toxicity, leading to hypercalcemia and associated complications.

Review Questions

• What role does cholecalciferol play in calcium metabolism?
• How is Vitamin D3 synthesized in the body?
• What are potential health consequences of both deficiency and excess intake of Vitamin D3?

Related terms

Calcitriol: The active form of Vitamin D3 that regulates calcium and phosphorus homeostasis.

Hypercalcemia: A condition characterized by elevated levels of calcium in the blood, often due to excessive Vitamin D intake.

Osteomalacia: A condition resulting from Vitamin D deficiency in adults, leading to softened bones.