Dietary fiber and the glycemic index: a background paper for the Nordic Nutrition Recommendations 2012

Abstract

The aim of this study is to review recent data on dietary fiber (DF) and the glycemic index (GI), with special focus on studies from the Nordic countries regarding cardiometabolic risk factors, type 2 diabetes, cardiovascular disease, cancer, and total mortality. In this study, recent guidelines and scientific background papers or updates on older reports on DF and GI published between 2000 and 2011 from the US, EU, WHO, and the World Cancer Research Fund were reviewed, as well as prospective cohort and intervention studies carried out in the Nordic countries. All of the reports support the role for fiber-rich foods and DF as an important part of a healthy diet. All of the five identified Nordic papers found protective associations between high intake of DF and health outcomes; lower risk of cardiovascular disease, type 2 diabetes, colorectal and breast cancer. None of the reports and few of the Nordic papers found clear evidence for the GI in prevention of risk factors or diseases in healthy populations, although association was found in sub-groups, e.g. overweight and obese individuals and suggestive for prevention of type 2 diabetes. It was concluded that DF is associated with decreased risk of different chronic diseases and metabolic conditions. There is not enough evidence that choosing foods with low GI will decrease the risk of chronic diseases in the population overall. However, there is suggestive evidence that ranking food based on their GI might be of use for overweight and obese individuals. Issues regarding methodology, validity and practicality of the GI remain to be clarified.

Carbohydrate quality, weight change and incident obesity in a Mediterranean cohort: the SUN Project

“…However, there is no agreement on which is the best measure of the quality of carbohydrates, although GI and glycemic load (GL) have been widely used. 15. However, recent 14 controversies about GI suggest that fibre and whole grain could also be good markers of carbohydrate quality and they can even superior to GI of GL.…”

“…The main criteria are related to whole grains consumption, dietary fibre intake, the solid or liquid form of carbohydrates and the GI. 14,15 To the best of our knowledge, no previous studies have examined in a multidimensional way, (i.e., taking into account at the same time several concepts including the glycemic index (GI), fibre content, solid or liquid form and the degree of processing), the effect of the nutritional quality of carbohydrates on weight gain or obesity in an adult population. Thus, the purpose of the present study was to examine the association between the overall dietary quality of carbohydrates and the average yearly weight change or the risk of becoming overweight/obese in a large prospective Mediterranean cohort.…”

Dietary fibre and health in children and adolescents

“…We have collected information on dietary recommendations from several countries ( Table 1). In addition to six mainstream English-speaking countries (Australia, Canada, Ireland, New Zealand, UK and USA) from which recommendations (8,13,16,32,33) and surveys (34)(35)(36)(37)(38)(39)(40)(41)(42) were retrieved, five additional recommendations (12,14,15,43,44) and five nutrition surveys (45)(46)(47)(48)(49) were obtained. Five papers (23,31,45,50,51) where recommendation and/or intakes were discussed were also included.…”

Do Norwegians with diabetes have a healthier diet than the general population?

“…Even though the intake of fiber did not reach recommended levels in any of the diabetes groups, patients with diabetes seem to have a higher intake of fiber than the controls. Sufficient intake of fiber is important as reviews of evidence conclude that increased intake of fiber reduces the risk of cardiovascular disease (CVD), colorectal and breast cancer (46) in addition to type 2 diabetes (9). High fiber diets may also improve glycaemic control and reduce number of hypoglycaemic events (8).…”