As an increasingly large body of research points to the benefits of vitamin D, health experts are suggesting some U.S. teenagers are not getting enough of the sunshine vitamin.

A group of scientists meeting at the Workshop Consensus for Vitamin D Nutritional Guidelines are suggesting the minimum acceptable level be increased to 20 ng/mL from 11 ng/mL.

Using these new standards as a guideline, they found that as many as one in seven American adolescents are deficient in vitamin D. More than half of African-American young people fall into this category, with girls and overweight teens especially at risk.

Dr. Sandy Saintonge of Weill Cornell Medical College suggested vitamin D nutritional supplements and increased education about food-based sources may be two ways to address this deficiency.

“We need to do a better job of educating the public on the importance of vitamin D,” she said. “We should also consider a national fortification strategy, perhaps including routine supplementation.”

Fish – including salmon, tuna and mackerel – is considered to be the best food source, while small amounts can also be found in eggs, cheese and fortified milk.