Analysis of the SYSDIET Healthy Nordic Diet randomized trial based on metabolic profiling reveal beneficial effects on glucose metabolism and blood lipids.
Study Goal
The researchers aimed to assess the effects of a healthy Nordic diet (including low-fat dairy) on metabolic profiles and cardiometabolic markers compared to a control diet.
Results Summary
The study found that the healthy Nordic diet (including low-fat dairy) was distinguishable from the control diet via metabolic profiles, with associations to improved HDL, triglycerides, and glucose metabolism. Dairy-specific effects were not isolated but contributed to the overall dietary pattern.
Population
200 participants with metabolic syndrome across six centers.
Effective Dosage
Not specified (dietary advice included low-fat dairy as part of the Nordic diet).
Duration
18-24 weeks.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
healthy Nordic diet (HND) | neutral | plasma metabolic profile | participants with metabolic syndrome | AUC of 0.96 ± 0.03 | distinguished from Control diet (CD) | #1 |
healthy Nordic diet (HND) | neutral | urine metabolic profile | participants with metabolic syndrome | AUC of 0.93 ± 0.02 | distinguished from Control diet (CD) | #2 |
healthy Nordic diet (HND) | neutral | markers of fish, whole grain and polyunsaturated lipids | participants with metabolic syndrome | - | characterized by | #3 |
Control diet (CD) | neutral | lipids containing palmitoleic acid | participants with metabolic syndrome | - | reflected by | #4 |
healthy Nordic diet (HND) | increase | HDL | participants with metabolic syndrome | β = 0.05; 95% CI: 0.02, 0.08; P = 0.001 | associated with | #5 |
healthy Nordic diet (HND) | decrease | triglycerides | participants with metabolic syndrome | β = -0.06; 95% CI: -0.09, -0.03; P < 0.001 | associated with | #6 |
healthy Nordic diet (HND) | increase | 2 h Glucose | participants with metabolic syndrome | β = 0.1; 95% CI: 0.05, 0.15; P < 0.001 | related with | #7 |
healthy Nordic diet (HND) | increase | LDL | participants with metabolic syndrome | β = 0.06; 95% CI: 0.01, 0.1; P = 0.02 | related with | #8 |
healthy Nordic diet (HND) | increase | triglycerides | participants with metabolic syndrome | β = 0.11; 95% CI: 0.06, 0.15; P < 0.001 | related with | #9 |
healthy Nordic diet (HND) | neutral | LDL cholesterol | participants with metabolic syndrome | - | related with | #10 |
BACKGROUND & AIMS: Intake assessment in multicenter trials is challenging, yet important for accurate outcome evaluation. The present study aimed to characterize a multicenter randomized controlled trial with a healthy Nordic diet (HND) compared to a Control diet (CD) by plasma and urine metabolic profiles and to associate them with cardiometabolic markers. METHODS: During 18-24 weeks of intervention, 200 participants with metabolic syndrome were advised at six centres to eat either HND (e.g. whole-grain products, berries, rapeseed oil, fish and low-fat dairy) or CD while being weight stable. Of these 166/159 completers delivered blood/urine samples. Metabolic profiles of fasting plasma and 24 h pooled urine were analysed to identify characteristic diet-related patterns. Principal components analysis (PCA) scores (i.e. PC1 and PC2 scores) were used to test their combined effect on blood glucose response (primary endpoint), serum lipoproteins, triglycerides, and inflammatory markers. RESULTS: The profiles distinguished HND and CD with AUC of 0.96 ± 0.03 and 0.93 ± 0.02 for plasma and urine, respectively, with limited heterogeneity between centers, reflecting markers of key foods. Markers of fish, whole grain and polyunsaturated lipids characterized HND, while CD was reflected by lipids containing palmitoleic acid. The PC1 scores of plasma metabolites characterizing the intervention is associated with HDL (β = 0.05; 95% CI: 0.02, 0.08; P = 0.001) and triglycerides (β = -0.06; 95% CI: -0.09, -0.03; P < 0.001). PC2 scores were related with glucose metabolism (2 h Glucose, β = 0.1; 95% CI: 0.05, 0.15; P < 0.001), LDL (β = 0.06; 95% CI: 0.01, 0.1; P = 0.02) and triglycerides (β = 0.11; 95% CI: 0.06, 0.15; P < 0.001). For urine, the scores were related with LDL cholesterol. CONCLUSIONS: Plasma and urine metabolite profiles from SYSDIET reflected good compliance with dietary recommendations across the region. The scores of metabolites characterizing the diets associated with outcomes related with cardio-metabolic risk. Our analysis therefore offers a novel way to approach a per protocol analysis with a balanced compliance assessment in larger multicentre dietary trials. The study was registered at clinicaltrials.gov with NCT00992641.