Apples could reduce risk of diabetes

An apple a day could keep diabetes away, according to a new report.

Research showed that eating whole fruits - particularly blueberries, grapes and apples - was ‘significantly associated’ with a lower risk of type 2 diabetes.

However, drinking more fruit juice was linked to an increased risk of developing the condition, reports the British Medical Journal.

Scientists suggest that this may be because healthy nutrients are lost in the juicing process while sugar is absorbed more rapidly into the blood from liquids.

Our findings provide novel evidence suggesting that certain fruits may be especially beneficial for lowering diabetes risk.”

Researchers looked at data from more than 187,000 people, gathered between 1984 and 2008.

More than 12,000 of these developed diabetes during the study period.

The researchers looked at overall fruit consumption, as well as consumption of individual fruits.

These were grapes or raisins, peaches, plums, apricots, prunes, bananas, cantaloupe melon, apples or pears, oranges, grapefruit, strawberries and blueberries.

Word of warning: Professor Qi Sun, pictured, of Brigham Women's Hospital in the United States, said: 'While fruits are recommended as a measure for diabetes prevention, previous studies have found mixed results for total fruit consumption'

They also looked at consumption of apple, orange, grapefruit, and “other” fruit juices.

People who ate at least two servings each week of certain whole fruits - particularly blueberries, grapes, and apples - reduced their risk for type 2 diabetes by as much as 23% in comparison to those who ate less than one serving per month.

Conversely, those who consumed one or more servings of fruit juice each day increased their risk of developing type 2 diabetes by as much as 21%. 

The researchers found that swapping three servings of juice per week for whole fruits would result in a 7% reduction in diabetes risk.

The fruits’ glycemic index (a measure of how rapidly carbohydrates in a food boost blood sugar) did not prove to be a significant factor in determining a fruit’s association with type 2 diabetes risk. 

However, the high glycemic index of fruit juice - which passes through the digestive system more rapidly than fiber-rich fruit - may explain the positive link between juice consumption and increased diabetes risk.

The researchers theorize that the beneficial effects of certain individual fruits could be the result of a particular component.

Previous studies have linked anthocyanins found in berries and grapes to lowered heart attack risk, for example. But more research is necessary to determine which components in the more beneficial fruits influence 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.”