Medical Research: What is the background for this study? What are the main findings?
Response: There are more than 360 million people worldwide that are affected by diabetes, and this number is projected to increase to more than 550 million by 2030, with serious consequences for the health and economy of both developed and developing countries. While previous research has found an association between increased dietary fibre intake and a reduced risk of developing type 2 diabetes, most of these data come from the United States, and amounts and sources of fiber intake differ substantially between countries. In this article the we evaluated the associations between total fiber as well as fiber from cereal, fruit, and vegetable sources, and new-onset type 2 diabetes in a large European cohort across eight countries, in the EPIC-InterAct Study (and included 12403 type 2 diabetes cases and 16835 sub-cohort members). We also conducted a meta-analysis where we combined the data from this study with those from 18 other independent studies from across the globe.
We found that participants with the highest total fiber intake (more than 26 g/day) had an 18% lower risk of developing diabetes compared to those with the lowest total fiber intake (less than 19g/day), after adjusting for the effect of other lifestyle and dietary factors. When the results were adjusted for body mass index (BMI) as a marker of obesity, higher total fiber intake was found to be no longer associated with a lower risk of developing diabetes, suggesting that the beneficial association with fiber intake may be mediated at least in part by BMI. In other words, dietary fiber may help people maintain a healthy weight, which in turn reduces the chances of developing type 2 diabetes.
In a meta-analysis of the EPIC-InterAct study and 18 other independent studies (>41000 type 2 diabetes cases) we found that the risk was reduced by 9% for each 10 g/day increase in total fiber intake and 25% for each 10 g/day increase in cereal fiber intake. There was no statistically significant association between fruit or vegetable fiber intake and diabetes.
Medical Research: What should clinicians and patients take away from your report?
Response: The current study suggest that people can reduce their risk of type 2 diabetes by increasing fiber intake. Since the association appeared to be driven mostly by cereal fiber intake, increasing intake of cereal fiber may be particularly important to reduce the risk of type 2 diabetes. Previous research has suggested that a high intake of whole grains may reduce type 2 diabetes risk and the current findings on cereal fiber are consistent with these findings.
Medical Research: What recommendations do you have for future research as a result of this study?
Response: Any additional studies could further investigate the association between fiber intake and types of fiber and diabetes risk in different geographic locations as well as further try to clarify the mechanisms by which fiber may reduce diabetes risk.
The InterAct Consortium. Dietary fibre and incidence of type 2 diabetes in eight European countries: the EPIC-InterAct Study and a meta-analysis of prospective studies. Diabetologia, May 2015 DOI: 10.1007/s00125-015-3585-9
MedicalResearch.com Interview with: Dagfinn Aune, PhD student, Norwegian University of Science and Technology and, & Imperial College London (2015). Dietary Fiber May Reduce Risk Of Diabetes MedicalResearch.com