BackgroundDifferent healthy food patterns may modify cardiometabolic risk. We investigated the effects of an isocaloric healthy Nordic diet on insulin sensitivity, lipid profile, blood pressure and inflammatory markers in people with metabolic syndrome.MethodsWe conducted a randomized dietary study lasting for 18–24 weeks in individuals with features of metabolic syndrome (mean age 55 years, BMI 31.6 kg m−2, 67% women). Altogether 309 individuals were screened, 200 started the intervention after 4-week run-in period, and 96 (proportion of dropouts 7.9%) and 70 individuals (dropouts 27%) completed the study, in the Healthy diet and Control diet groups, respectively. Healthy diet included whole-grain products, berries, fruits and vegetables, rapeseed oil, three fish meals per week and low-fat dairy products. An average Nordic diet served as a Control diet. Compliance was monitored by repeated 4-day food diaries and fatty acid composition of serum phospholipids.ResultsBody weight remained stable, and no significant changes were observed in insulin sensitivity or blood pressure. Significant changes between the groups were found in non-HDL cholesterol (−0.18, mmol L−1 95% CI −0.35; −0.01, P = 0.04), LDL to HDL cholesterol (−0.15, −0.28; −0.00, P = 0.046) and apolipoprotein B to apolipoprotein A1 ratios (−0.04, −0.07; −0.00, P = 0.025) favouring the Healthy diet. IL-1 Ra increased during the Control diet (difference −84, −133; −37 ng L−1, P = 0.00053). Intakes of saturated fats (E%, beta estimate 4.28, 0.02; 8.53, P = 0.049) and magnesium (mg, −0.23, −0.41; −0.05, P = 0.012) were associated with IL-1 Ra.ConclusionsHealthy Nordic diet improved lipid profile and had a beneficial effect on low-grade inflammation.

Our study suggests that a 5-week high dietary fiber intake of oat bran, rye bran, and sugar beet fiber might reduce the low-grade inflammatory response measured as CRP which could, together with reduced fibrinogen, help to prevent the risk of cardiovascular disease.

The present review examines the evidence regarding the effect of β‐glucan on variables linked to the metabolic syndrome (MetS), including appetite control, glucose control, hypertension, and gut microbiota composition. Appetite control can indirectly influence MetS by inducing a decreased energy intake, and promising results for a β‐glucan intake to decrease appetite have been found using gut hormone responses and subjective appetite indicators. Beta‐glucan also improves the glycemic index of meals and beneficially influences glucose metabolism in patients with type 2 diabetes or MetS, as well as in healthy subjects. Furthermore, a blood‐pressure‐lowering effect of β‐glucan in hypertensive subjects seems fairly well substantiated. The gut microbiota composition might be an interesting target to prevent MetS, and preliminary results indicate the prebiotic potential of β‐glucan. The evidence that β‐glucan influences appetite control and gut microbiota in a positive way is still insufficient or difficult to interpret, and additional studies are needed in this field. Still, much evidence indicates that increased β‐glucan intake could prevent MetS. Such evidence should encourage increased efforts toward the development of β‐glucan‐containing functional foods and promote the intake of β‐glucan‐rich foods, with the aim of reducing healthcare costs and disease prevalence.

The objective was to investigate the alterations of plasma metabolome profiles to identify exposure and effect markers of dietary fiber intake. Subjects (n = 25) aged 58.6 (1.1) years (mean and SD) with a body mass index of 26.6 (0.5) kg/m(2) were given a high fiber (HF) and a low fiber (LF) diet, in a 5-week randomized controlled crossover intervention. The HF diet consisted of oat bran, rye bran, and sugar beet fiber incorporated into test food products, whereas the LF diet was made of equivalent food products to the HF diet, but without adding fibers. Blood plasma samples were collected at the start and end of each intervention period and analyzed by LC-QTOF/MS. In total, 6 features in positive mode and 14 features in negative mode were significantly different between the HF and the LF diet (p < 0.01, q < 0.05). Two markers, 2,6-dihydroxybenzoic acid and 2-aminophenol sulfate, were increased after HF diet, along with a tentatively identified saponin derived from oat avenacosides. The untargeted metabolomics approach enabled the identification of two new markers of dietary fiber intake in human plasma. Further studies will be needed to verify if these markers could serve as compliance markers of fiber intake.