We all need vitamin D, as well as calcium, for building strong bones. But evidence has been accumulating that “D” plays a much wider role in health, including protecting against certain cancers and multiple sclerosis, and according to new research, optimizing lung function. Researchers from the Harvard School of Public Health recently reported that teenagers who consumed less than the RDA of 200 IU of vitamin D had lower lung function than teens getting the RDA. Researchers found that 35 percent of the 2,112 teens participating in the study consumed less than the RDA of vitamin D and that they had significantly lower lung function than their peers who consumed 200 IU or more. Lead researcher Jane Burns noted that less-than-optimal lung function during adolescence might have long-term health effects. Vitamin D can be produced in the skin in response to sunlight but this effect is blocked by sunscreen. “D” is also found in fortified dairy products, egg yolks, salmon, mackerel and sardines. The study was presented on May 22, 2006, at the American Thoracic Society’s International Conference.