Vitamin D: The Rickets Analogy

By | October 17, 2011

Many physicians recommend vitamin D supplementation to everyone using the chicken soup principle of medicine, “It couldn’t hurt.” This may not be the best approach.

Much of what we know about the therapeutic uses of vitamin D come from work in the early part of the 20th century on the pediatric bone disease, rickets. This disease is characterized by very low levels of vitamin D, leading to impaired absorption of calcium in the gut. This leads to weak and deformed bones, but rarely to fractures or chronic pain. Serum calcium and phosphate levels are often low and in some cases clinical signs of hypocalcemia including neuromuscular hyperexcitability and cardiac arrhythmias may develop.

It is dangerous to assume that he effects of vitamin D on osteoporosis will be similar. Osteoporosis is a disease of adults, characterized by the demineralization of once normal bones. The bones are usually normally shaped except where arthritis and fractures, which are common in this disease, have distorted them. Serum calcium and phosphate levels are usually normal in osteoporosis. Finally, while vitamin D supplementation has been shown to be beneficial in cases of severe deficiency, results have been inconsistent and often contradictory in cases of mild deficiency or in cases where serum vitamin D levels are “normal”.

Because acute vitamin D toxicity is difficult to produce and requires extremely high levels of ingestion, many physicians recommend vitamin D supplementation to everyone using the chicken soup principle of medicine, “It couldn’t hurt.” In some of the following blogs we will examine some of the direct effects of vitamin D on bone metabolism in adults and see why this type of reasoning is best left to grandmothers.


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