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Purpose: Evidence of an association between n-3 polyunsaturated fatty acids (PUFAs) and metabolic syndrome (MS) is limited and inconsistent. We investigated the association between n-3 PUFAs in erythrocytes and the presence of MS in Chinese adults. Methods: The levels of α-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA) in erythrocytes were measured using gas chromatography in 3072 participants (900 men and 2172 women) aged 30-75 years from Guangzhou, China. Cardiometabolic factors were determined, and MS was defined using the updated Adult Treatment Panel III criteria. Other covariates were collected via interviewer-administered questionnaires. Results: After adjusting for age and other confounders, higher levels of marine-derived n-3 PUFAs, including EPA, DPA, and DHA, were associated with a lower presence of metabolic syndrome in both men and women. The odds ratios (95 % confidence interval) for MS obtained by comparing extreme quartiles were 0.55 (0.35-0.88) (EPA), 0.54 (0.34-0.87) (DPA), 0.45 (0.27-0.73) (DHA), and 0.52 (0.32-0.84) (total n-3 PUFAs) in men ( p trend <0.05 for all results); and 0.74 (0.56-0.99) (EPA), 0.73 (0.55-0.98) (DPA), 0.75 (0.56-1.02) (DHA), and 0.71 (0.53-0.96) (total n-3 PUFAs) in women, respectively. No significant association of ALA with MS was observed ( p trend > 0.05). Conclusion: Higher levels of total n-3 PUFAs, EPA, DPA, and DHA, but not of ALA, in erythrocyte membranes are associated with a lower presence of metabolic syndrome in Chinese adults. [ABSTRACT FROM AUTHOR]

Purpose: The associations between specific carotenoid intake and colorectal cancer risk remain inconsistent. The aim of this study was to examine the association between specific dietary carotenoid intake with colorectal cancer risk in Chinese adults. Method: From July 2010 to October 2013, 845 eligible colorectal cancer cases and 845 frequency-matched controls (age and sex) completed in-person interviews. A validated food frequency questionnaire was used to estimate dietary intake. Multivariate logistical regression models were used to calculate the odds ratio (OR) and 95 % confidence intervals (95 % CIs) of colorectal cancer risk after adjusting for various confounders. Results: A strong inverse association was found between β-cryptoxanthin intake and colorectal cancer risk. Compared with the lowest quartile, the highest quartile intake showed a risk reduction of 77 % (OR 0.23, 95 % CI 0.17-0.33, P < 0.01) after adjustment for various confounding variables. The inverse associations were also observed for α-carotene (OR 0.50, 95 % CI 0.37-0.68, P < 0.01), β-carotene (OR 0.67, 95 % CI 0.49-0.91, P < 0.01), and lycopene (OR 0.51, 95 % CI 0.37-0.70, P < 0.01). There was no statistically significant association between lutein/zeaxanthin intake and colorectal cancer risk. These findings were consistent across cancer site, sources of controls, and smoking status. The inverse associations between dietary α-carotene, β-cryptoxanthin, and lycopene intake and colorectal cancer risk were found in both males and females, while inverse associations between β-carotene intake and colorectal cancer risk were only observed in males. Conclusions: Consumption of α-carotene, β-carotene, β-cryptoxanthin, and lycopene was inversely associated with colorectal cancer risk. No significant association was found between lutein/zeaxanthin intake and colorectal cancer risk. [ABSTRACT FROM AUTHOR]

Purpose: This study was to evaluate the associations of dietary intake of total and specific phytosterols and risk of esophageal squamous cell carcinoma (ESCC) and to explore their joint effects with PLCE1 rs2274223 polymorphisms. Methods: A population-based case–control study was conducted in a Chinese rural population and 856 eligible incident ESCC cases and 856 controls were included. A validated food frequency questionnaire was used to collect dietary consumption and PLCE1 rs2274223 polymorphisms were genotyped. Unadjusted and adjusted odds ratios (ORs) with 95% confidence interval (CI) were assessed via logistic regression model. Results: When comparing the highest with lowest intake quartiles, β-sitosterol, campesterol, stigmasterol, β-sitostanol, campestanol, and total phytosterols were all associated with a decreased risk of ESCC, with adjusted ORs being 0.32 (95% CI 0.20–0.48), 0.18 (95% CI 0.11–0.27), 0.45 (95% CI 0.29–0.70), 0.13 (95% CI 0.08–0.20), 0.14 (95% CI 0.09–0.22) and 0.28 (95% CI 0.18–0.43), respectively. An exposure—response relationship was also observed for both total and five specific phytosterols (all P for trend < 0.001). In comparison to rs2274223 AA genotype, both GA genotype (OR: 1.47, 95% CI 1.16–1.85) and GG genotype (OR: 2.13, 95% CI 1.20–3.84) were associated with an increased risk of ESCC. However, no interaction was observed between total/specific phytosterols intake and rs2274223 polymorphisms. Conclusion: Higher dietary intake of total and five specific phytosterols was associated with a lower risk of ESCC, and the risk of ESCC increased with the increment of rs2274223 G allele. The negative association between phytosterols and ESCC risk was not modified by rs2274223 polymorphisms. Foods or supplements rich in phytosterols are a promising source for chemoprevention of ESCC, and still, clinical trials will be required in any specific case. [ABSTRACT FROM AUTHOR]

Purpose: Previous studies have shown that high-dose supplementation with n-3 polyunsaturated fatty acids (PUFAs) may benefit patients with nonalcoholic fatty liver disease (NAFLD), but the association of n-3 PUFAs with NAFLD among individuals with normal diets is only speculative. We investigated the cross-sectional and prospective associations between n-3 PUFAs and NAFLD in Chinese adults. Methods: This community-based prospective study included 3049 men and women (40–75 years) in Guangzhou, China, whose participants completed an NAFLD ultrasound evaluation and erythrocyte PUFA tests. A total of 2660 participants underwent the second NAFLD evaluation approximately 3 years later. α-Linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in erythrocytes were measured by gas chromatography. Results: After adjusting for potential confounders, we observed inverse associations between DHA, DHA + EPA, total n-3 PUFAs and the presence of NAFLD in the cross-sectional analysis. The adjusted odds ratios (95% confidence interval) of NAFLD for the highest (vs. lowest) tertile were 0.74 (0.61, 0.90) for DHA, 0.82 (0.67, 1.00) for EPA, 0.73 (0.60, 0.88) for DHA + EPA and 0.74 (0.61, 0.91) for total n-3 PUFAs (all P values≤0.05). Over the average 3.12 years of follow-up, higher levels of DHA was associated with an improvement of NAFLD. The hazard ratio of improved NAFLD for the highest tertile was 1.18 (95% CI 1.09, 1.33) for DHA. Pathway analyses showed that favorable associations may be mediated by improvements in inflammatory markers (e.g., interleukin 1 beta and tumor necrosis factor alpha-like). Conclusions: Erythrocyte membrane n-3 PUFAs are inversely associated with the presence and progression of NAFLD in Chinese adults. Trial registrations: ClinicalTrials.gov NCT03179657. [ABSTRACT FROM AUTHOR]

Purpose: Many studies have examined the association of isoflavone intake with type 2 diabetes (T2D), and produced inconsistent results. Few studies, however, explored the association using objective biomarkers (particular for daidzein metabolite-equol) of isoflavones. We aimed to explore the association of urinary equol, daidzein and genistein concentrations with T2D and examine the mediating roles of high-sensitivity C-reactive protein (hsCRP) and retinol binding protein 4 (RBP4). Methods: This prospective study included 2818 subjects. Urinary concentrations of equol, daidzein and genistein were measured by high-performance liquid chromatography-tandem mass spectrometry. The associations between urinary isoflavones and T2D incidence were evaluated by cox proportional hazards model. Results: After adjustment for covariates, urinary equol except daidzein and genistein was inversely associated with T2D incidence. In comparison with the first tertile, multivariable adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs) for T2D incidence in the second and third tertile of equol concentration were 0.52 (0.37, 0.73) and 0.72 (0.53, 0.97), respectively. In stratified analyses by sex, the HR (95% CI) of men in the second vs. first tertile of equol was 0.29 (0.14, 0.58). Equivalent estimation in women was 0.67 (0.45, 1.01). Neither women nor men in the third tertile showed significant difference of T2D incidence compared with the first tertile. In path analyses, there was no evidence of mediating effects of hsCRP and RBP4 on the "equol-T2D" relationship. Conclusions: Urinary equol was favorably associated with a decreased T2D incidence in Chinese adults. The equol–T2D relationship might not be mediated by hsCRP and RBP4. Trial registration: This study has been registered at http://www.clinicaltrials.gov as NCT03179657. [ABSTRACT FROM AUTHOR]

Purpose: Higher levels of fatty acids (FAs) in the de novo lipogenesis (DNL) pathway might be associated with higher levels of fat mass (FM), while limited evidence is available from the general population. We aimed to examine the associations between DNL-FAs and body fat and fat distribution in a general population of Chinese adults. Methods: This community-based prospective cohort study included 3,075 participants (68% women) aged 40–75 years in urban Guangzhou, China. We measured erythrocyte DNL-FAs composition (including C16:0, C16:1n-7, C18:0, and C18:1n-9) at baseline and %FM over the total body (TB), trunk, limbs, android (A) and gynoid (G) regions after 3.2 years and 6.3 years of follow-up, respectively. Results: Generally, higher proportions of individual erythrocyte DNL-FAs and their combined index were positively associated with adipose indices in the multivariable cross-sectional and longitudinal analyses. The cross-sectional percentage mean differences in quartile 4 (vs. 1) of the DNL index were 3.43% (TB), 4.56% (trunk), and 2.67% (A/G ratio) (all P trends < 0.01). The corresponding values in longitudinal changes of adipose indices were 1.40% (TB), 1.78% (trunk), and 1.32% (A) (all P trends < 0.05). The above associations tended to be more pronounced in the trunk and android area than the limbs and gynoid area. Conclusions: Erythrocyte DNL-FAs may contribute to an increase in total body fat in Chinese adults, particularly FM distributed in trunk and abdominal regions. [ABSTRACT FROM AUTHOR]

Purpose: Previous studies have suggested that serum carotenoids might be inversely associated with non-alcoholic fatty liver disease (NAFLD), but little data came from longitudinal studies. We prospectively examined the associations between serum-carotenoid levels and NAFLD severity and the intermediary effects of retinol-binding protein 4 (RBP4), HOMA insulin-resistance index (HOMA-IR), body mass index (BMI), and serum triglycerides in middle-aged and elderly Chinese adults. Methods: This prospective study included 3336 Chinese adults (40–75 years). We assessed serum concentrations of carotenoids at baseline and determined serum RBP4, triglycerides, and HOMA-IR levels at year 3. Abdominal ultrasonography was conducted to assess the presence and degree of NAFLD at years 3 and 6. Results: The 2687 subjects who completed both NAFLD tests were classified into stable, improved and progressed groups according to changes in the degree of NAFLD between two visits. Analyses of covariance showed that ln-transformed serum concentrations of α-carotene, β-cryptoxanthin, β-carotene, lycopene, lutein/zeaxanthin, and total carotenoids were positively associated with NAFLD improvement (all p-trend < 0.05). After multivariable adjustment, mean differences in serum carotenoids were higher by 29.6% (β-carotene), 18.2% (α-carotene), 15.6% (β-cryptoxanthin), 11.5% (lycopene), 8.9% (lutein/zeaxanthin), and 16.6% (total carotenoids) in the improved vs. progressed subjects. Path analyses indicated the carotenoid–NAFLD association was mediated by lowering serum RBP4, triglycerides, HOMA-IR, and BMI, which were positively associated with the prevalence and progression of NAFLD. Conclusions: In middle-aged and elderly adults, higher serum-carotenoid concentrations were favorably associated with NAFLD improvement, mediated by reducing serum RBP4, triglycerides, HOMA-IR, and BMI. Trial registrations: This study has been registered at http://www.clinicaltrials.gov as NCT03179657. [ABSTRACT FROM AUTHOR]

Objective: Previous studies suggested that magnesium (Mg) might protect against atherosclerosis, but data were scarce in an Asian population. We examined the association of Mg levels in serum and urine with carotid intima-media thickness (cIMT) and serum lipids in Chinese adults. Methods: This community-based cross-sectional study recruited 2,837 participants aged 40-75 years in Guangzhou, China. General information, lifestyle factors, serum and urinary concentrations of Mg and cardiometabolic factors were determined. The cIMTs of the common carotid artery (CCA) and the carotid bifurcation (BIF) were measured ultrasonographically. Results: The mean (SD) concentration of serum Mg was 0.85 (0.07) mmol/L and median (IQR) for urinary Mg excretion was 2.29 (1.56-3.51) mmol/L. After adjustment for potential covariates, both serum and the urinary concentrations of Mg were inversely associated with CCA-IMT, but not with BIF-IMT. The regression coefficients (standard errors) were −100 (29) µm (total), −86 (34) µm (women) and −117 (52) µm (men) CCA-IMT per 1 mmol/L of serum Mg, and −41 (8) µm (total), −41 (10) µm (women) and −44 (15) µm (men) CCA-IMT per 1 unit of urinary Mg/creatinine (log mmol/mmol) (all p < 0.05), respectively. Higher serum Mg levels were associated with higher total cholesterol, HDLc, LDLc and triglyceride, but lower non-HDLc/HDLc in total population (all p < 0.05). Similar relationships of urinary Mg with lipoproteins were also found in total population (all p < 0.05). Conclusion: Higher levels of serum and urinary Mg are associated with lower CCA-IMTs, and the role of Mg in lipid metabolism needs further investigation. [ABSTRACT FROM AUTHOR]