Association of exposure to polycyclic aromatic hydrocarbons with thyroid hormones in adolescents and adults, and the influence of the iodine status.

Some studies of endocrine-disrupting polycyclic aromatic hydrocarbon (PAH) exposure and thyroid hormones (THs) are inconclusive. To assess the associations between PAHs and THs, and the influence of the iodine status on PAHs-THs, we employed 648 adolescents (12-19 years old) and 2691 adults from the National Health and Nutrition Examination Survey 2007-2008 and 2011-2012. PAH metabolites [1-hydroxynaphthalene (1-NAP), 2-NAP, 1-hydroxyphenanthrene (1-PHE), 2-PHE, 3-PHE, 2-hydroxyfluorene (2-FLU), 3-FLU, 9-FLU, and 1-hydroxypyrene (1-PYR)], THs [total and free thyroxine (TT4 and FT4), total and free triiodothyronine (TT3 and FT3), thyroid stimulating hormone (TSH), and thyroglobulin (Tg)], peripheral deiodinase activity (GD) and thyroid's secretory capacity (GT) were involved. Multiple linear regression and weighted quantile sum (WQS) regression models were used to assess PAH-TH associations and the interaction between PAHs and the iodine status. Stratification analyses were conducted based on sex, smoking and iodine status. For adolescents, in a multivariable-adjusted regression model (ß; 95% CI), 1-PHE (4.08%; 1.01%, and 7.25%), 2-PHE (3.98%; 0.70%, and 7.25%) and 9-FLU (3.77%; 1.10%, 7.47%) were positively correlated with TT3; 3-PHE and 1-PYR interacted with the iodine status (P-int < 0.05); 9-FLU was positively correlated with GD in both sexes. Combined exposure to PAHs was positively associated with Tg (0.137; 0.030, and 0.243), and negatively correlated with TSH (-0.087; -0.166, and -0.008). For adults, 2-NAP was positively correlated with FT3 (0.90%; 0.20%, and 1.61%), FT4 (1.82%; 0.70%, and 2.94%), TT3 (1.31%; 0.10%, and 2.63%), TT4 (2.12%; 0.90%, and 3.36%) and GT (2.22%; 1.01%, and 3.46%), but negatively correlated with TSH (-4.97%; -8.33%, and -1.49%); 1-NAP interacted with the iodine status (P-int < 0.05); 1-PHE was inversely correlated with TT3 in males; 2-PHE was positively correlated with TT3 in females. Combined exposure to PAHs was positively associated with FT3 (0.008; 0.001, and 0.014). Combined exposure to PAHs was positively associated with FT3, TT3 and GD, and negatively correlated with FT4, TT4 and GT in non-smoking adults; but positively associated with Tg (ß = 0.140; 95% CI: 0.042, 0.237) in smoking adults. Our results indicated that combined and individual PAH exposure might be related to THs, and the iodine status had an influence on PAH-TH associations. These associations were not identical between adolescents and adults, and there were sex and smoking status differences.

Adults allostatic load is less with greater dietary quality: National Health and Nutrition Examination Survey (NHANES) 2015-2018.

BACKGROUND AND OBJECTIVES: Few studies have explored the relationship between overall diet quality and stress load. Therefore, we have evaluated the association between dietary quality and allostatic load (AL) in adults. METHODS AND STUDY DESIGN: The data were derived from the 2015-2018 National Health and Nutri-tion Examination Survey (NHANES). Dietary intake information was obtained by 24-hour dietary recall. The Healthy Eating Index (HEI) 2015 version was estimated as an indicator of dietary quality. The AL was in-dicative of the accumulated chronic stress load. The weighted logistic regression model was used to explore the relationship between dietary quality and the risk of high AL in adults. RESULTS: A total of 7557 eligible adults older than 18 years were enrolled in this study. After being fully adjusted, we found a significant asso-ciation between HEI score and the risk of high AL (ORQ2 =0.73, 95% CI: 0.62,0.86; ORQ3 =0.66, 95% CI: 0.55,0.79; ORQ4 =0.56, 95% CI: 0.47,0.67) in logistic regression model. Increased intake of total fruits and whole fruits or decreased intake of sodium, refined grains, saturated fats and added sugars were associated with the risk of high AL (ORtotal fruits =0.93, 95%CI: 0.89,0.96; ORwhole fruits =0.95, 95%CI: 0.91,0.98; ORwhole grains =0.97, 95%CI: 0.94,0.997; ORfatty acid =0.97, 95%CI: 0.95,0.99; ORsodium =0.95, 95%CI: 0.92,0.98; ORre-fined grains =0.97, 95%CI: 0.94,0.99; ORsaturated fats =0.96, 95%CI: 0.93,0.98; ORadded sugars =0.98, 95%CI: 0.96,0.99). CONCLUSIONS: We found that dietary quality was inversely associated with allostatic load. High di-etary quality presumptively less cumulative stress.

The Mediating Effect of Central Obesity on the Association between Dietary Quality, Dietary Inflammation Level and Low-Grade Inflammation-Related Serum Inflammatory Markers in Adults.

To date, few studies have explored the role of central obesity on the association between diet quality, measured by the health eating index (HEI), inflammatory eating index (DII), and low-grade inflammation-related serum inflammatory markers. In this paper, we use the data from the 2015-2018 National Health and Nutrition Examination Survey (NHANES) to explore this. Dietary intakes were measured during two 24-h dietary recall interviews and using USDA Food Pattern Equivalence Database (FPED) dietary data. Serum inflammatory markers were obtained from NHANES Laboratory Data. Generalized structural equation models (GSEMs) were used to explore the mediating relationship. Central obesity plays a significant mediating role in the association between HEI-2015 and high-sensitivity C-reactive protein (hs-CRP), mediating 26.87% of the associations between the two; it also mediates 15.24% of the associations between DII and hs-CRP. Central obesity plays a mediating role in 13.98% of the associations between HEI-2015 and white blood cells (WBC); it also mediates 10.83% of the associations between DII and WBC. Our study suggests that central obesity plays a mediating role in the association of dietary quality with low-grade inflammation-related serum inflammatory markers (hs-CRP and WBC).

The Chain-Mediating Effect of Obesity, Depressive Symptoms on the Association between Dietary Quality and Cardiovascular Disease Risk.

In order to explore the relationship between the Healthy Eating Index (HEI-2015) and cardiovascular disease (CVD), and the mediating role of obesity and depressive symptoms, we used the data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) for further study. A total of 12,644 participants were included in the study. The HEI was derived using NHANES personal food data and USDA Food Pattern Equivalence Database (FPED) dietary data. The risk of cardiovascular disease was determined using the Framingham Heart Study's multifactorial calculation tool. The weighted multiple logistic regression model was used to explore the association between the HEI-2015 and CVD, and the generalized structural equation was used to explore the mediating effects of obesity and depression, respectively and jointly. Higher HEI-2015 scores were associated with a lower risk of CVD compared to lower quartiles. Obesity, depressive symptoms, and their chain effects all played significant mediating roles in the association between the HEI-2015 and CVD, with proportional mediations of 9.03%, 2.23% and 0.25%, respectively. Our results suggest that higher dietary quality is associated with a lower risk of CVD, mediated by obesity, depressive symptoms, and the chain effect of obesity and depressive symptoms.

Association between perfluoroalkyl substances exposure and the prevalence of nonalcoholic fatty liver disease in the different sexes: a study from the National Health and Nutrition Examination Survey 2005-2018.

There is evidence that perfluoroalkyl substances (PFASs) have effects on liver toxicity, and the effects may exhibit sex differences. Our study aims to explore the association between exposure to four PFASs (perfluorooctanoic acid, PFOA; perfluorooctane sulfonate, PFOS; perfluorohexane sulfonate, PFHxS; and perfluorononanoate, PFNA) and the risk of nonalcoholic fatty liver disease (NAFLD) in adults ≥ 20 years old in the US population. The data were based on the National Health and Nutrition Examination Survey (NHANES) 2005-2018. We used Poisson regression to explore the association between the four PFASs and NAFLD. We included 3464 participants; of these, 1200 (34.64%) individuals were defined as having NAFLD, and the prevalence of NAFLD was 39.52% in men and 30.40% in women. After Poisson regression, among the premenopausal and postmenopausal and total women, PFOA had a significantly positive association with NAFLD (p < 0.05). After principal component analysis, the "composite PFAS" was associated with NAFLD in postmenopausal and total women, and the RRs (95% CIs) were 1.306 (1.075, 1.586) and 1.161 (1.007, 1.339), respectively. In adults, we found that PFASs were associated with NAFLD, and the associations varied by sex, particularly for PFOA and PFNA, which had a positive association with NAFLD in women.