A study published in The American Journal of Clinical Nutrition (January 2015 vol. 101) has found that a healthy Nordic diet reduces inflammatory gene expression in abdominal fat tissue compared with a control diet independent of body weight changes.

Previously, a healthy Nordic diet (ND) has been shown to have beneficial health effects close to those of Mediterranean diets. This newly published study was part of the Nordic SYSDIET Study.

Participants (200) were middle-aged men and women exhibiting at least two characteristics of metabolic syndrome, such as elevated blood pressure or fasting blood sugar levels, abnormal blood lipid values, or at least slight overweight. These conditions can often occur together and can increase your risk of Type 2 diabetes, stroke and heart disease.

Researchers from all the Nordic countries led by Marjukka Kolehmainen, University of Eastern Finland, Institute of Public Health and Clinical Nutrition, had an objective to explore whether the ND has an impact on gene expression in abdominal subcutaneous adipose tissue (SAT) and whether changes in gene expression are associated with clinical and biochemical effects.

In the study, obese adults with features of the metabolic syndrome underwent an 18-to-24-week randomized intervention study comparing the Nordic Diet with the control diet (CD) (the SYSDIET study, carried out within Nordic Centre of Excellence of the Systems Biology in Controlled Dietary Interventions and Cohort Studies).

For 18 to 24 weeks, half of the participants followed the health-promoting Nordic diet consisting of whole grain products, vegetables, root vegetables, berries, fruit, low-fat dairy products, rapeseed oil and three servings of fish per week. The control group consumed low-fibre grain products, butter-based spreads, and had a limited intake of fish.

The participants were asked to maintain their body weight unchanged during the intervention, and no significant weight changes occurred during the study period. Samples of the study participants’ adipose tissue were taken at the beginning and end of the study, and a transcriptomics analysis was performed in order to study the expression of genes.

Differences in the function of as many as 128 different genes were observed in the adipose tissue of the health-promoting Nordic diet group and the control group. In the health-promoting Nordic diet group, the expression of several inflammation-associated genes was lower than in the control group.

According to the study the fact that diet can be used to affect the function of inflammation-associated genes without weight loss is significant. The study sheds further light on the significance of diet in the healing of low-grade inflammation, which is associated with several chronic diseases.

The researchers concluded that a healthy Nordic diet reduces the expression of genes involved in inflammation in subcutaneous adipose tissue in individuals with features of the metabolic syndrome.