Next big thing: ‘Nordic Diet’, Researchers show health benefit for the obese without weight loss
The Nordic diet may reduce the bad effects of obesity, even without weight loss, according to a study led by the Institute of Public Health and Clinical Nutrition at the University of Eastern Finland.
The study, published recently in the American Journal of Clinical Nutrition, found that the Nordi diet reduced the expression of inflammation-associated genes in subcutaneous adipose tissue. In overweight persons, the expression of these genes reduced without weight loss. To a certain extent, the adverse health effects of overweight are believed to be caused by an inflammatory state in adipose tissue.
The Nordic diet consists of whole grain products, vegetables, root vegetables, berries, fruit, low-fat dairy products, rapeseed oil and three servings of fish per week.
Researchers on the study said being overweight was associated with problems in sugar and lipid metabolism as well as with atherosclerosis, and that these may be caused by a low-grade inflammatory state resulting from disturbed adipose tissue function. The researchers said long-term research into the role of diet in the function of adipose tissue genes and inflammatory state was scarce.
The study was part of the Nordic SYSDIET Study. The objective was to find out whether the health-promoting Nordic diet affects the expression of genes in adipose tissue without weight loss. The study participants 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.
For a period of 18 to 24 weeks, half of the study participants followed the ‘health-promoting’ Nordic diet. The control group consumed low-fibre grain products, butter-based spreads, and had a limited intake of fish.
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 gene function recorded
The researchers said 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. The researchers said it was “significant” that the diet could be used to affect the function of inflammation-associated genes without weight loss. They said the study shed further light on the significance of diet in the healing of low-grade inflammation, which is associated with several chronic diseases.
The main funders of the study were The NordForsk grant for the Systems Biology in Controlled Dietary Interventions and Cohort Studies (SYSDIET) for 2007–2012 (SYSDIET; 070014). The study also received funding from several Nordic funders of science, including the Academy of Finland, the Royal Swedish Academy of Sciences, the Danish Council for Strategic Research, and several private scientific foundations operating in the Nordic Countries.