A diet high in fatty fish, bilberries and wholegrain products improves markers of endothelial function and inflammation in individuals with impaired glucose metabolism in a randomised controlled trial: The Sysdimet study

Abstract

Aims/hypothesis Low-grade inflammation and endothelial dysfunction may play a role in the pathogenesis of type 2 diabetes and cardiovascular disease. We evaluated whether a diet high in fatty fish, bilberries and wholegrain products (Healthy Diet) improves biomarkers reflecting inflammation and endothelial dysfunction in individuals with impaired glucose metabolism. Methods We recruited individuals with impaired glucose metabolism and features of the metabolic syndrome into a 12 week, parallel design, dietary intervention trial conducted at the Department of Clinical Nutrition, University of Eastern Finland (Kuopio, Finland). Randomisation was performed by matching according to sex and medians of age, BMI and fasting plasma glucose of the study population at screening. The primary endpoint in the present study was the change in plasma inflammatory markers and the measurements were performed blinded to group assignment. High-sensitivity (hs) C-reactive protein (CRP) and E-selectin responses were also analysed separately in participants not using statins (n=76). Results Altogether, 131 individuals were assigned to either the Healthy Diet (n=44), a whole-grain-enriched diet (WGED) (n= 42) or a control (n =45) diet, and 104 participants (mean±SD: age 59±7 years; BMI 31.1± 3.5 kg/m 2 ) who had completed the study, were analysed (Healthy Diet n=36, WGED n=34 and control diet n=34). Plasma E-selectin decreased only in the Healthy Diet group. This occurred in all group participants (p<0.05) and also after excluding participants using statins (p<0.05). Plasma hsCRP levels decreased in the Healthy Diet (median −17%, p<0.05) and WGED (median −27%, p<0.01) groups in participants not using statins. Controlling for confounding factors, including BMI or insulin sensitivity, did not alter the results. A greater increase in plasma concentration of very-long-chain n-3 fatty acids and in the intake of fibre Electronic supplementary material The online version of this article (doi:10.1007/s00125-011-2285-3) contains peer-reviewed but unedited supplementary material, which is available to authorised users.

Anbefalt nordisk kosthold og risikomarkører for hjerte- og karsykdom

“…This result is consistent with the absence of effect on glucose and insulin sensitivity in the SYSDIET and SYSDIMET studies, where the participants maintained a stable weight throughout the study period (15,19). In the NND study, plasma metabolome analyses (measurement of all types of metabolites in plasma) that linked weight changes and improved insulin sensitivity to metabolic processes such as increased ketosis and increased gluconeogenesis were also undertaken (23).…”

“…The 15 articles (13 -27) that were included are based on four randomised, controlled dietary intervention studies (Table 1) (13,15,18,19,28,29). These studies were conducted in Sweden (NORDIET) on persons with moderately elevated cholesterol levels; in Denmark (New Nordic Diet, NND) on overweight people; and in Finland (SYSDIMET) on moderately overweight people with reduced glucose metabolism.…”

“…In the SYSDIMET study (19), the serum level of E-selectin was significantly reduced with a diet based on oily fish, blueberries and wholegrain cereals (p = 0.04). There was also a significant reduction in the level of highsensitivity CRP (hsCRP) of 0.3 mg/l within the group that ate wholegrain cereals (p = 0.02).…”

“…The SYSDIMET study (19) The participants were advised about what to eat, and products were provided.…”

The Baltic Sea Diet Score: a tool for assessing healthy eating in Nordic countries

“…Although many Nordic foods are considered to have health benefits, only little is known about the healthrelated effects of the Nordic diet in its entirety (13)(14)(15)(16)(17) . Furthermore, the Nordic nutrition recommendations are based on single food-and nutrient-oriented research and give guidelines regarding these (18) .…”