A vitamin D deficiency causes brittle, misshapen bones and can lead to rickets. Sufficient Vitamin D and calcium help protect the bones against osteoporosis. A lack of vitamin D in adulthood can cause a condition known as osteomalacia, also called adult rickets. Symptoms of osteomalacia include weak bones and muscles. What causes vitamin D deficiency?
People get vitamin D from their diets and sunlight. Vitamin D is found in dairy products fortified with vitamin D. Some grains like bread are also fortified with vitamin D. When people do not drink or eat dairy or grain products fortified with vitamin D or do not spend time outdoors, they are susceptible to vitamin D deficiency.
A few other foods contain vitamin D. Egg yolks, though often avoided due to cholesterol, contain a small amount of vitamin D. Cheese, some mushrooms, some brands of orange juice, and beef liver also contain some vitamin D. Fish and fish liver oils contain vitamin D as well. A vitamin D deficiency develops over time of not having enough vitamin D. It is not a condition that has a sudden onset.
Dairy foods in the United States began to be fortified with vitamin D in the 1930s in response to the rickets epidemic at that time. This dairy product vitamin D fortification program is credited with much of the success of practically eliminating rickets from the United States.
Ultraviolet rays in sunlight cause a natural reaction in the body called vitamin D synthesis. Though people may think that a person must spend a significant amount of time in the sun to prevent a vitamin D deficiency, as little as ten minutes daily is considered to be enough to prevent a vitamin D deficiency.
Some medical conditions can increase the risk of a vitamin D deficiency. Obesity, Crohn’s disease, and inflammatory bowel disease can contribute to vitamin D deficiencies. People with cystic fibrosis or fat malabsorption syndromes are prone to vitamin D deficiencies. Since people who are lactose intolerant may avoid consuming dairy foods, they may be susceptible to a vitamin D deficiency.
The elderly are also susceptible to vitamin D deficiency. In rare cases, an abnormally low metabolism of vitamin D is genetic. In those cases, there is a hereditary inability to metabolize enough vitamin D. In addition to preventing skeletal deformities, vitamin D may protect the body from some cancers, high blood pressure, and some autoimmune diseases.