A: Vitamin D is a fat soluble vitamin that has several important functions in the body. It helps the body absorb calcium and phosphorus and suppresses a hormone that causes calcium leeching from the bones. Vitamin D appears to serve important functions in the body’s immune, heart and muscle function as well, but more research is needed to substantiate this.
Vitamin D is acquired through diet and through adequate exposure to sunlight. Unfortunately, at latitudes and climates such as central Iowa, sunlight exposure is often insufficient to sustain the body’s vitamin D need. Individuals, who do not get enough vitamin D from their diet then become vitamin D deficient. The most serious complication of this is low blood calcium and phosphate, rickets and osteomalacia (softening of the bones in childhood and adulthood respectively). More common is “subclinical” vitamin D deficiency, or vitamin D deficiency without visible signs or symptoms. This is associated with reduced bone density (osteopenia or osteoporosis), a slight decrease of the blood calcium, elevated parathyroid hormone (which accelerates bone breakdown) and weakened bones, which fracture more easily.
Vitamin D deficiency can be diagnosed by a simple blood test, but testing is not recommended in everyone. Treatment of vitamin D deficiency is typically with vitamin D3, and treatment dose depends on the degree of the deficiency. In adults with normal vitamin D3 levels, 800 international units daily is recommended to prevent defficiency. Children and infants should receive 400 international units daily. Certain medical conditions alter the body’s ability to process and utilize vitamin D such as kidney or liver disease and certain gastrointestinal and skin disorders. Your primary care physician will be able to determine if you are at risk and if testing and treatment are needed.
Information provided Einar Arason, D.O., Family Physicians at Prairie Trail, 2515 S.W. State St., 964-6999.