Background and aims: In a cross-European study it was recently shown that consumption of cod increases weight loss in men and also has other positive health effects. The aim of this study was to investigate whether cod consumption increases weight loss and improves cardiovascular risk factors in a dose dependent manner during an 8-week energy restriction diet in young overweight and obese healthy adults.
Methods and results: In this dietary intervention 126 subjects (20-40 years, BMI 27.5-32.5 kg/m(2)) comprised the group given energy-restricted diets (-30%); they were prescribed an identical macronutrient composition but different amounts of cod: the control group were given no seafood; group 1 were given 150 g cod 3 times a week; and group 2 were given 150 g cod 5 times a week. Anthropometric measurements and cardiovascular risk factors were assessed at baseline and endpoint. Body weight decreased after 8-weeks (5.0+/-2.9 kg, P<0.001), also waist circumference (5.0+/-3.2 cm, P<0.001), BMI (1.65+/-0.95 kg, P<0.001), systolic (3.4+/-8.9 mmHg, P=0.001) and diastolic blood pressure (2.4+/-6.9 mmHg, P<0.001), triglycerides (1.26+/-0.567 mmol/L, P=0.030) and insulin (1.21+/-5.31 mU/L, P=0.025). The prevalence of the metabolic syndrome dropped from 29 to 21%. According to linear models weight loss was 1.7 kg greater among subjects consuming 150 g 5x/week compared to the control group (P<0.015). The trend analysis supported a dose-response relationship between cod consumption and weight loss (P<0.001), but changes of other measured cardiovascular risk factors were similar between the groups.
Conclusion: A dose-response relationship between cod consumption and weight loss during an 8-week energy restriction diet is found and 5 x 150 g cod/week results in 1.7 kg greater weight loss in young overweight or obese adults than a isocaloric diet without seafood.