In a review article to appear in the July 19th issue of the New England Journal of Medicine, Dr. Michael Holick, an internationally recognized expert in vitamin D, provides an overview of his pioneering work that expounds on the important role vitamin D plays in a wide variety of chronic health conditions, as well as suggesting strategies for the prevention and treatment of vitamin D deficiency.
Humans attain vitamin D from exposure to sunlight, diet and supplements. Vitamin D deficiency is common in children and adults. In utero and childhood, vitamin D deficiency may cause growth retardation, skeletal deformities and increase risk of hip fractures later in life. In adults, vitamin D deficiency may precipitate or exacerbate osteopenia, osteoporosis, muscle weakness, fractures, common cancers, autoimmune diseases, infectious diseases and cardiovascular diseases.
According to Holick, a professor of medicine, physiology, and biophysics, and director of the General Clinical Research Center at Boston University School of Medicine and Director of the Bone Healthcare Clinic at Boston Medical Center, it has been estimated that 1 billion people world-wide are vitamin D deficient or insufficient.
Without vitamin D only about 10-15 percent of dietary calcium and about 60 percent of phosphorus is absorbed by the body. This is directly related to bone mineral density which is responsible for osteoporosis and fractures, as well as muscle strength and falls in adults. In utero and childhood, calcium and vitamin D deficiency prevents the maximum deposition of calcium in the skeleton.