Blueberries, grapes, and apples offer the strongest health benefits.Science is finding more health benefits from blueberries—but raising more concerns about fruit juice. According to a new study by Harvard University researchers, eating whole fruits helps ward off diabetes, while drinking juice can actually raise the risk of developing the disease.In a study published in the British Medical Journal, nutrition experts report that consumption of certain fruits—especially blueberries—cut people’s risk of type 2 diabetes by as much as 26 percent in a survey of more than 180,000 subjects over two and a half decades.Study participants were asked about their consumption of...