Image of Nicola Bondonno, Ph.D.

People who consume at least two daily servings of fruit have higher insulin sensitivity and 36% lower odds of developing type 2 diabetes than their peers who eat a half-serving each day, according to nutrition researchers.

The investigators examined fruit and fruit juice intake and the five-year prevalence of diabetes in more than 7,600 Australians participating in a population-based study.

“We found an association between fruit intake and markers of insulin sensitivity, suggesting that people who consumed more fruit had to produce less insulin to lower their blood glucose levels,” said lead author Nicola Bondonno, Ph.D., from the Institute for Nutrition Research, Edith Cowan University, in Australia.

“This is important because high levels of circulating insulin (hyperinsulinemia) can damage blood vessels and are related not only to diabetes, but also to high blood pressure, obesity, and heart disease,” she said.

Although it is not yet clear how fruit intake affects diabetes risk, a variety of factors likely contribute, including certain vitamins and minerals, phytochemicals that may increase insulin sensitivity, and fruit fiber, which helps to regulate the release of sugar into the blood and may also bring about a feeling of “fullness” that helps prevent overeating, she said.

Fruit juice did not have the same benefits as whole fruits, however, most likely because juices typically are much higher in sugar content and lower in fiber, Bondonno said. Many fruits also have a low glycemic index when compared with fruit juice, meaning that their sugar is digested and absorbed into the body more slowly, helping the body regulate insulin, she added.

The study was published in the Journal of Clinical Endocrinology and Metabolism.