Vitamin D
Function
Vitamin D has properties of both a vitamin and a hormone. It is required for the absorption and utilization of calcium and phosphorus, two of the primary building blocks of bone. It is involved in the regulation of the heartbeat. There are two forms of vitamin D; D2 (ergocaliciferol), which comes from food sources and vitamin D3 (cholecalciferol) that is synthesized in the skin in response to skin exposure. Vitamin D3 is considered the most active form and is the preferred supplemental form.
Sources
Dietary sources of Vitamin D are fish liver oils, fatty saltwater fish, dairy products, eggs, and dandelion greens. Sunlight is also a source of vitamin D.
Deficiency
Severe deficiency can cause rickets in children. Lesser deficiency symptoms may be loss of appetite, burning sensation in the mouth and throat, diarrhea, insomnia, visual problems, and weight loss.