Study Suggests 2 Servings of Fruit Per Day Cuts Odds of Developing Diabetes by 36%

Nicola Bondonno, PhD

New research from Edith Cowan University in Australia is providing evidence of the impact lifestyle intervention can have on the health of at-risk patient populations.

An analysis of data from participants within the Australian Diabetes, Obesity, and Lifestyle Study, results indicate patients consuming 2 or more servings of fruit daily had 36% lower odds of developing diabetes in the next 5 years than their counterparts who consumed half a serving or less daily.

"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 Nicola Bondonno, PhD, study lead investigator and Adjunct Lecturer at Edith Cowan University's Institute for Nutrition Research in Perth, Australia, in a statement. "This is important because high levels of circulating insulin can damage blood vessels and are related not only to diabetes, but also to high blood pressure, obesity, and heart disease.”

With the going prevalence of obesity and diabetes posing a significant public health burden, studies aimed at understanding avenues of mitigating this risk have received a greater emphasis in recent years. To learn more about dietary mechanisms related to fruit intake, Bondonno and a team of colleagues designed the current study as an analysis of data from participants within the Australian Diabetes, Obesity, and Lifestyle Study.

A national population-based survey of Australian adults, the study provided information related to more than 11,000 patients recruited between 1999-2000 and followed through 2012 for potential inclusion in their analyses. Using only those with complete data, including information from food frequency questionnaires, and who were free from diabetes at baseline, investigators identified a cohort of 7675 patients for inclusion in their analyses. Of note, 3518 patients had data available from the 12-year follow-up and 4674 had data available from the 5-year follow-up.

The overall study cohort had a mean age of 54±12 years at baseline, 45% were male, the mean BMI was 26.8±4.7 kg/m2, 48% had a physical activity level considered insufficient or sedentary, and the median total fruit intake was 162 (IQR, 95-283) g/day). Compared to those in the lowest quartile of total fruit intake, those with the greatest intake were more likely to be female, older, more physically active, less disadvantaged, have a higher level of education, and were less likely to be smokers.

Investigators used restricted cubic splines in logistic and linear regression models to evaluate associations fasting plasma glucose (FPG), 2-hour postload plasma glucose, updated homeostasis model assessment of insulin resistance of β-cell function (HOMA2-%β), HOMA2 of insulin sensitivity (HOMA2-%S), and fasting insulin levels at baseline and the presence of diabetes at the 5- and 12-year follow-ups.

Analysis of baseline data indicated total fruit intake was inversely associated with serum insulin and HOMA2-%β. Investigators also noted total fruit intake was positively associated with HOMA2-%S at baseline. Further analysis indicated those with moderate (quartile 3) total fruit intake had 36% lower odds of developing diabetes at 5 years. However, investigators pointed out associations with 12-year outcomes and total fruit intake were not statistically significant.

"We did not see the same patterns for fruit juice. These findings indicate that a healthy diet and lifestyle which includes the consumption of whole fruits is a great strategy to lower your diabetes risk,” added Bondonno, in a statement from The Endocrine Society.

This study, “Associations Between Fruit Intake and Risk of Diabetes in the AusDiab Cohort,” was published in the Journal of Clinical Endocrinology & Metabolism.