Teenage girls (especially athletes) need Vitamin D Calcium and dairy products are needed for strong, healthy bones and teeth. However, recent research published in the Archives of Pediatrics & Adolescent Medicine shows that vitamin D intake is a very essential nutrient for strong bones. The researchers, who came from various medical establishments in Boston, MA, followed over 6700 girls between the ages of 9 and 15, from 1996-2001. A questionnaire, was sent at 12-24 month intervals, asking about dietary intake of calcium, dairy and vitamin D along with stress fracture incidence. It was found,that those with a higher intake of vitamin D, had a lower risk of stress fractures. Stress fractures are a common injury for athletes, especially teenage girls. They are caused by high levels of pressure or stress on the bone and can sometimes develop over time, even without any noticeable injury. The scientists discovered that girls involved in more than one hour a day of a high stress activity were especially protected by vitamin D intake. We know that severe Vitamin D deficiency results in rickets, a serious disease, which prevents mineralization of the bones and results in skeletal deformities. It is now being discovered that less severe deficiencies can result in weaker bones that are more prone to stress and injury. Previous studies have shown that vitamin D deficiency in individuals over 50 leads to increased risk of fractures, however, this recent research shows that younger individuals are also very susceptible to fractures due to vitamin D deficiency. This is likely because vitamin D is necessary for the proper use of calcium and phosphorus in the bone. Vitamin D dosage and sources of vitamin D The RDA for vitamin D was set at 600 IU for individuals between 1 and 70 years of age in November 2010. However, many medical professionals believe that these levels are too low. The best way to determine how much vitamin D one needs for optimal health is to have blood levels checked. Individual needs are determined by how much one manufactures from the sun or gets from food sources. The sun is obviously the largest source of vitamin D. However, how much vitamin D you are able to produce from the sun depends on your skin tone, degree of latitude, amount of skin exposure and time of day. It should also be noted that sunscreens that block ultra-violet rays, also block the production of vitamin D. Food sources of vitamin D include egg yolk, fish, fish oil, cod liver oil, cheese and beef liver. Further research needs to be done. However, this study clearly shows the importance of proper vitamin D intake for young, female athletes.