Effect of fatty fish or nut consumption on concentrations of persistent organic pollutants in overweight or obese men and women: A randomized controlled clinical trial.

BACKGROUND AND AIMS: While excess energy intake and physical inactivity constitute the obvious causes of body fat accumulation, persistent organic pollutants (POPs) are novel factors that have been linked to cardiometabolic disorders. Major sources of POPs are animal fats including fatty fish. Given the putative protective effects of fish on cardiovascular disease, we explored whether high consumption of fatty fish increased serum concentrations of POPs. METHODS AND RESULTS: Men and women aged 35-70 years with body mass index between 25 and 38 kg/m2 and at least 1 cardiometabolic component were randomized to high intakes of fatty fish (mostly farmed salmon, ∼630 g/week; n = 45), high intakes of nuts (∼200 g/week; n = 42) or a control group following their usual diet but restricting fatty fish and nuts for 6 months (n = 44). Concentrations of 15 POPs (5 organochlorinated compounds, 2 dioxin-like polychlorinated biphenyls and 8 non-dioxin-like polychlorinated biphenyls) and cardiometabolic risk factors were measured at baseline and end of the study. Results showed that changes in concentrations of individual and classes of POPs did not differ between the dietary groups and controls (p > 0.05). Among cardiometabolic risk factors HDL-cholesterol increased in the fatty fish group compared to controls (+0.10 mmol/L, CI (0.05-0.20); p = 0.005) while no changes were observed in the group consuming nuts. CONCLUSION: Fatty fish consumption for 6 months did not increase the serum concentrations of POPs in individuals with overweight or obesity and metabolic risk. While this finding appears reassuring regarding short-term intakes of farmed salmon, long term variations in POPs in adipose stores require further study.

Associations of Circulating PYY3-36 Concentrations with Metabolic Syndrome in Extremely Obese Subjects.

BACKGROUND: The gut hormone peptide YY3-36 (PYY3-36) plays major roles in regulation of appetite and energy metabolism, mediates beneficial effects of bariatric surgery, and may be a potential weight-reducing and glucose-modulating therapy. Obesity may influence the metabolic expression of circulating PYY3-36 and metabolic markers. We studied the relationship of PYY3-36 concentrations with metabolic syndrome (MetSyn) components, lipids, insulin resistance, and inflammatory biomarkers in subjects with extreme obesity. METHODS: We measured MetSyn components and PYY3-36, lipids, hormones, homeostasis model assessment (HOMA) index, and inflammatory biomarkers in consecutively referred patients (180 women and 111 men) aged 18-78 years with body mass index (BMI) ≥40 kg/m2. Associations of PYY3-36 to components, insulin resistance, and biomarkers were examined with partial correlations and linear regression. RESULTS: PYY3-36 concentrations were not related to MetSyn components, HOMA index, or to inflammatory biomarker or leptin concentrations. PYY3-36 concentrations correlated with systolic blood pressure (r = 0.21; P < 0.0001) after adjustment for age and gender. In linear regression analysis, PYY3-36 concentrations were associated with systolic blood pressure after adjustment for age, gender, and central obesity in the entire sample (Beta 0.21; 95% CI 0.09-0.34) as well as in subjects not taking blood pressure-lowering medication (Beta 0.19; 95% CI 0.04-0.36). These associations were not statistically significant in the small subset of participants (22%) with type 2 diabetes. CONCLUSIONS: In extremely obese patients, fasting PYY3-36 concentrations were linked to systolic blood pressure, but not to other components of MetSyn, suggesting divergence between pathways of blood pressure and glucose/body weight regulation. However, this finding will need to be further investigated.

Characteristics of Metabolic Syndrome in Morbidly Obese Subjects.

BACKGROUND: Metabolic syndrome (MetSyn) magnifies risks of cardiovascular disease (CVD) and type 2 diabetes, but its expression varies within the obese population. We examined body mass index (BMI), metabolic traits, and fat distribution in morbidly obese individuals. METHODS: Lipids and inflammatory, oxidative stress and hepatic biomarkers in 346 women and 203 men (BMI ≥35 kg/m2 and co-morbidity or ≥40 kg/m2) were stratified by MetSyn components (1-5, excluding diabetes). Age- and smoking-adjusted partial correlations were calculated. Dual-energy X-ray absorptiometry was measured in 206 participants. RESULTS: Apolipoprotein B, ferritin, uric acid, and alanine aminotransferase (ALT) concentrations worsened with increasing MetSyn components (P ≤ 0.0001), while BMI and LDL-cholesterol showed no association. BMI correlated inversely with triglycerides (r = -0.16, P = 0.03) and positively with HDL-cholesterol in men (r = 0.16, P = 0.02), but not in women. BMI correlated with C-reactive protein (CRP) (r = 0.32, P < 0.0001; r = 0.24, P < 0.0001 in men and women, respectively) and white blood cell count (r = 0.24, P = 0.001 in men; r = 0.15, P = 0.008 in women). Truncal fat percentage correlated to CRP (r = 0.31, P = 0.03; r = 0.20, P = 0.02 in men and women, respectively). In women, number of MetSyn components was inversely related to truncal and peripheral fat (r = -0.20, P = 0.02; r = -0.42, P < 0.0001, respectively) as was ALT (r = -0.21, P = 0.009; r = -0.38, P < 0.0001, respectively) and triglycerides with peripheral fat (r = -0.38, P < 0.0001), while HDL cholesterol was positively associated with truncal and peripheral fat (r = 0.26; P = 0.001). CONCLUSIONS: BMI and fat distribution showed expected associations to inflammation biomarkers, but paradoxical relations between fat indices, and MetSyn components and biomarkers were seen. This suggests a need for better markers of CVD risk in morbid obesity.