For some reason which continues to elude me, people are eating less and less fruit – but perhaps the increasing consumption of juice has something to do with this. Now, a new study led by Harvard School of Public Health researchers has shown that eating more fruits, particularly blueberries, grapes, and apples, was associated with a significantly lower risk of type II diabetes, while the consumption of fruit juice was associated with an increase in this risk.
“While fruits are recommended as a measure for diabetes prevention, previous studies have found mixed results for total fruit consumption. Our findings provide novel evidence suggesting that certain fruits may be especially beneficial for lowering diabetes risk,” said senior author Qi Sun, assistant professor in the Department of Nutrition at HSPH and assistant professor of medicine at the Channing Division of Network Medicine, Brigham and Women’s Hospital.
Researchers analyzed a huge amount of data (187,382 participants) gathered from 1984 and 2008; any participants who reported a diagnosis of diabetes, cardiovascular disease, or cancer at enrollment were excluded. Results showed that 12,198 participants (6.5 percent) developed diabetes during the study period.
They then analyzed overall fruit consumption, as well as individual fruit consumption: apples, pears, peaches, plums, apricots, bananas, cantaloupe, oranges, grapefruits, strawberries, blueberries, grapes and raisins – nothing was spared. They also analyzed how much fruit juice the subjects drank.
People who ate at least two servings each week of certain whole fruits (most notably blueberries, grapes, and apples, though all fruits showed positive effects) reduced their risk for type 2 diabetes by as much as 23 percent in comparison to those who ate less than one serving per month. They also concluded that swapping three servings of juice per week for whole fruits would result in a 7 percent reduction in diabetes risk.
“Our data further endorse current recommendations on increasing whole fruits, but not fruit juice, as a measure for diabetes prevention,” said lead author Isao Muraki, research fellow in the Department of Nutrition at HSPH. “And our novel findings may help refine this recommendation to facilitate diabetes prevention.”