the dietary recommendation for vitamin D was recently _______ for infants, children and adolescents. A. eliminated B. doubled C. tripled D. quadrupled

B. doubled

Vitamin D is essential for maintaining healthy bones and teeth, supporting the immune system, and ensuring proper muscle function. It is unique because it can be synthesized by our bodies when the skin is exposed to sunlight. However, due to various factors such as lifestyle, geographic location, skin pigmentation, and concerns about skin cancer, many people do not receive adequate amounts from sunlight and must rely on dietary sources or supplements.

For infants, children, and adolescents, adequate vitamin D intake is crucial for the development of strong bones. Insufficient vitamin D can lead to rickets in children, a condition characterized by soft, weak bones that can lead to skeletal deformities. In adults, vitamin D deficiency can lead to osteomalacia, which causes bone pain and muscle weakness.

The dietary recommendations for vitamin D are issued by health organizations like the Institute of Medicine (IOM) in the United States. These recommendations provide guidance on the amount of vitamin D that should be consumed to maintain good health. The exact recommendation for vitamin D intake can vary based on factors such as age, sex, and life stage. When the recommendations are updated, as implied in the question, it is typically based on new research that suggests different amounts are necessary to maintain optimal health.

For specific guidelines, always refer to the latest recommendations from official sources like the IOM or national health organizations, as these guidelines can change over time with new evidence. Parents and caregivers should discuss their child's vitamin D needs with a healthcare provider to ensure they are getting the right amounts for their age and health status.