Conditions Caused By Vitamin D3 Deficiency

Vitamin D-3, or cholecalciferol, is known as the "sunshine vitamin," because it is synthesized in your skin when you are exposed to ultraviolet light. D-3 can also be obtained from supplements and foods such as egg yolks and cod liver oil. Once it enters your circulation, vitamin D-3 is converted in your liver and kidneys to the active form of vitamin D, 1,25-dihydroxyvitamin D. Although vitamin D's most notable effects are on bone growth and calcium metabolism, it also affects many other organ systems.

Rickets

Vitamin D-3 stimulates the absorption of calcium and phosphorous from your intestine, promotes the retention of calcium by your kidneys and regulates the mineralization of your bones. In growing children, vitamin D-3 deficiency causes abnormalities in the growth plates of the bones, resulting in scoliosis, delay in skeletal growth and difficulty walking. In cases of severe deficiency, bowlegs or "knock-knees" may develop, and seizures or other neurologic abnormalities can occur. This condition is called rickets. According to a 2004 review in "The American Journal of Clinical Nutrition," rickets often improves during the summer, when affected children are exposed to sunlight.

Osteomalacia and Osteoporosis

In adults whose growth plates have already fused, vitamin D-3 deficiency can lead to a condition called osteomalacia, which means "softening of the bones." The risks of osteomalacia mirror those of osteoporosis. An increased risk of fractures results from both conditions, and sometimes these fractures occur with minimal trauma, particularly in the elderly. Osteoporosis, or "porous bones," is also a frequent finding in vitamin D-deficient adults, as demonstrated by a 2011 study in "The Journal of Clinical Endocrinology and Metabolism," which showed that 90 percent of osteoporotic patients who experience fractures are vitamin D deficient.

Immune and Inflammatory Problems

The discovery that most of your cells possess receptors for vitamin D has opened new avenues of investigation regarding cholecalciferol's health benefits. Scientists have proposed that vitamin D deficiency might contribute to cardiovascular disease and autoimmune disorders, such as type 1 diabetes, multiple sclerosis, rheumatoid arthritis, Crohn's disease and ulcerative colitis. A 2005 study in "The Journal of Rheumatology" confirms that vitamin D is an important regulator of your immune system, and vitamin D-3 deficiency probably sets the stage for the development of a variety of chronic diseases.

Considerations and Recommendations

The importance of adequate vitamin D-3 intake extends beyond its effects on bone health. Acting like a hormone to stimulate receptors in a wide array of cells and tissues, vitamin D exerts effects on all of your organ systems. The full extent of its activity is only beginning to be understood. Currently, the recommended daily adequate intakes for vitamin D-3 vary from 200 IU for infants to 600 IU for adults, but many scientists, such as Dr. Reinhold Vieth at the University of Toronto, are urging higher doses -- at least twice the current recommendations -- for optimal health. Ask your doctor if you need to take additional vitamin D-3.