biostudies-literatureJaacks LMNational Center for Advancing Translational SciencesNCATS NIH HHSNational Institute of Diabetes and Digestive and Kidney DiseasesNIDDK NIH HHSNational Heart, Lung, and Blood InstituteNHLBI NIH HHSIntramural CDC HHS26https://www.ebi.ac.uk/biostudies/studies/S-EPMC6159217biostudies-literatureUnknown4<h4>Background</h4>The 2015-2020 Dietary Guidelines for Americans recommend a Mediterranean-type diet as one of three healthful eating patterns. However, only one previous trial has evaluated the effects of a Mediterranean diet intervention in a US sample population.<h4>Methods</h4>To address this gap, we conducted a pilot, non-blinded, 8-week randomized controlled trial on the comparative efficacy of consumption of a Mediterranean diet or a diet supplemented with fish oil, walnuts, and grape juice versus controls. Participants (overweight or obese US adults; 73% female and mean age 51 years) were randomly assigned to one of three groups: (1) Mediterranean diet; (2) habitual high-fat American-type diet supplemented with fish oil, walnuts, and grape juice; or (3) habitual high-fat American-type diet (controls). Intent-to-treat analysis of within-subject differences (Student's paired t-test or Wilcoxon sign ranks test) and between-subject differences (mixed-effects models with a group-by-time interaction term, adjusted for baseline health outcome) was conducted.<h4>Results</h4>Participants in the Mediterranean diet arm (<i>n</i> = 11) had significantly greater weight loss despite no significant change in total caloric intake, and lower plasma cystine, indicative of decreased oxidative stress, compared to controls (<i>n</i> = 9) at both 4 and 8 weeks. Compared to controls, they also had significantly lower total cholesterol and low-density lipoprotein cholesterol levels at 4 weeks. Participants in the supplement arm (<i>n</i> = 10) had significantly lower adiponectin levels compared to controls at 4 weeks. No significant improvements in endothelial function or inflammatory biomarkers were observed in either intervention group compared to controls.<h4>Conclusion</h4>These results suggest that adopting a dietary pattern reflecting a Mediterranean diet improves weight and cardio-metabolic health among overweight or obese US adults, and may be more beneficial than supplementing habitual American diets with fish oil, walnuts, and grape juice.BMC nutritionPilot randomized controlled trial of a Mediterranean diet or diet supplemented with fish oil, walnuts, and grape juice in overweight or obese US adults.PMC6159217U01 HL-079156P20 HL1134515P20HL113451-01UL1 TR0023781U10HL110302-01UL1 TR000454R56 HL126558K24 DK096574CC9999991R56HL126558-015P01HL101398-02P01 HL101398U10 HL110302U01 HL079156Staercke CJones DPVaccarino VQuyyumi AAPorkert MZiegler TRJaacks LMSher SAlexander WRfalsePilot randomized controlled trial of a Mediterranean diet or diet supplemented with fish oil, walnuts, and grape juice in overweight or obese US adults.<h4>Background</h4>The 2015-2020 Dietary Guidelines for Americans recommend a Mediterranean-type diet as one of three healthful eating patterns. However, only one previous trial has evaluated the effects of a Mediterranean diet intervention in a US sample population.<h4>Methods</h4>To address this gap, we conducted a pilot, non-blinded, 8-week randomized controlled trial on the comparative efficacy of consumption of a Mediterranean diet or a diet supplemented with fish oil, walnuts, and grape juice versus controls. Participants (overweight or obese US adults; 73% female and mean age 51 years) were randomly assigned to one of three groups: (1) Mediterranean diet; (2) habitual high-fat American-type diet supplemented with fish oil, walnuts, and grape juice; or (3) habitual high-fat American-type diet (controls). Intent-to-treat analysis of within-subject differences (Student's paired t-test or Wilcoxon sign ranks test) and between-subject differences (mixed-effects models with a group-by-time interaction term, adjusted for baseline health outcome) was conducted.<h4>Results</h4>Participants in the Mediterranean diet arm (<i>n</i> = 11) had significantly greater weight loss despite no significant change in total caloric intake, and lower plasma cystine, indicative of decreased oxidative stress, compared to controls (<i>n</i> = 9) at both 4 and 8 weeks. Compared to controls, they also had significantly lower total cholesterol and low-density lipoprotein cholesterol levels at 4 weeks. Participants in the supplement arm (<i>n</i> = 10) had significantly lower adiponectin levels compared to controls at 4 weeks. No significant improvements in endothelial function or inflammatory biomarkers were observed in either intervention group compared to controls.<h4>Conclusion</h4>These results suggest that adopting a dietary pattern reflecting a Mediterranean diet improves weight and cardio-metabolic health among overweight or obese US adults, and may be more beneficial than supplementing habitual American diets with fish oil, walnuts, and grape juice.2018-01-01T00:00:00Z20182024-12-03T17:40:26.917Z2020-05-22T12:16:42ZS-EPMC61592173027161010.1186/s40795-018-0234-y