Effects of a healthy Nordic diet on weight loss in adults: a systematic review and meta-analysis of randomized controlled clinical trials.
OBJECTIVES
Studies on the effect of the Nordic diet (ND) on body weight and adiposity indices were conflicting. This study targeted to perform a systematic review and meta-analysis of randomized controlled clinical trials (RCTs) examined the effect of the ND on body weight and composition.


METHODS
PubMed, Scopus, ISI web of Science, ProQuest and Google Scholar were searched for the eligible studies up to August 2019. The weighted mean difference (WMD) in body weight and composition indices between the ND and control groups/periods was derived using random-effects model.


RESULTS
In total, seven studies (n = 774 participants) were included in the present study. Five studies had illustrated the effect of the ND on weight, three on waist circumference (WC), two on body fat, and two on body mass index (BMI). The pooled analysis of eligible trials showed that those adhered to the ND lost 1.83 kg [95% confidence interval (CI) - 2.94, - 0.73, P = 0.001] more weight compared to controls. Qualitative assessment of other anthropometric indices also showed a beneficial effect of this dietary pattern in improving body fat and BMI values; however, these findings are not conclusive because of limited number of studies.


CONCLUSION
Adherence to the ND significantly improves body weight; however, there is also no certainty that this diet is effective for improving other anthropometric indices. Future studies regarding the effect of the ND on weight and body composition in populations other than Nordic populations are highly recommended. Level of evidence Level I, systematic reviews and meta-analyses.
['Ramezani-Jolfaie|Nahid|N|', 'Mohammadi|Mohammad|M|', 'Salehi-Abargouei|Amin|A|http://orcid.org/0000-0002-7580-6717']
D000328:Adult D015992:Body Mass Index D001835:Body Weight D004032:Diet D006801:Humans D055105:Waist Circumference D015431:Weight Loss
Nordic diet Systematic review Body weight Waist circumference Baltic Sea diet Body fat percent