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How Vitamin D Works

Vitamin D Deficiency
Although Vitamin D can be found in such everyday foods as milk, it's not always ingested at high enough amounts, resulting in a number of Vitamin D deficiency problems. These issues can include disorders such as rickets and osteomalacia.

Vitamin D deficiency in adults involves the loss of calcium and protein from bones.
©2007 Publications International, Ltd.
Vitamin D deficiency in adults involves the
loss of calcium and protein from bones.

Vitamin D deficiency causes rickets in children. Because vitamin D is crucial to proper calcium metabolism, the hallmark of rickets is the undermineralization and softening of bones. One of its common signs is bowlegs. Another sign is beadlike swellings on the ribs -- a condition called rachitic rosary. Teething is usually late in children with rickets, and what teeth do develop are susceptible to decay.

Though rickets is rare in the United States today, some cases do appear in low-income children, vegetarian children, infants who were breast-fed for an extended period of time with no supplementation, and in older adults who can no longer make vitamin D efficiently.

Vitamin D deficiency in adults results in a condition called osteomalacia. It involves the loss of calcium and protein from bones, due to insufficient vitamin D. Osteomalacia differs from osteoporosis in that bone loses only mineral. In osteoporosis, bone itself is lost. In developing countries, osteomalacia is prevalent in women who have low intakes of calcium and vitamin D, and several closely spaced pregnancies followed by long periods of breast-feeding.

If you're not getting enough vitamin D daily, you can increase your intake through taking supplements. In the next section, we'll discuss what types of supplements exist and how to know if you need to up your vitamin D dosage.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.