
The guidelines are the basis of everything from school lunch programs to the diets promoted in bestselling books, but in recent years some scientists have begun to question the one-size-fits-all approach.

"We're gonna ask Dunkin' Doughnuts and Starbucks, show us the safety data that shows that it's OK for a teenage girl to drink an iced coffee with 115 grams of sugar in it. I don't ...