Vitamin D

Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and multiple other biological effects. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol).

Sources of Vitamin D

The primary source of vitamin D is sunlight. When our skin is exposed to sunlight, it produces vitamin D. Additionally, vitamin D can be found in certain foods such as fatty fish (salmon, mackerel, sardines), beef liver, cheese, and egg yolks. Some foods, such as milk and orange juice, are fortified with vitamin D.

Functions of Vitamin D

Vitamin D plays a crucial role in maintaining the health of bones and teeth by aiding in the absorption of calcium and phosphorus. It also supports the immune system, muscle function, and helps reduce inflammation.

Deficiency and Toxicity

A deficiency in vitamin D can lead to bone deformities such as rickets in children and osteomalacia in adults. Conversely, excessive intake of vitamin D can lead to toxicity, resulting in symptoms such as nausea, vomiting, weakness, and kidney damage.

Study Guide

1. What are the primary sources of vitamin D?
2. What are the functions of vitamin D in the body?
3. What are the consequences of a vitamin D deficiency?
4. What are the potential risks of excessive vitamin D intake?
5. Discuss the role of vitamin D in bone health.