Associations of maternal serum concentration of iron-related indicators with birth outcomes in Chinese: a pilot prospective cohort study.

BACKGROUND: Previous studies of maternal iron and birth outcomes have been limited to single indicators that do not reflect the comprehensive relationship with birth outcomes. We aimed to investigate the relationship between maternal iron metabolism and neonatal anthropometric indicators using comprehensive iron-related indicators. METHODS: A total of 914 Chinese mother-child dyads were enrolled in this prospective study. Subjects' blood samples were collected at ≤ 14 weeks of gestation. Serum concentrations of iron-related indicators were measured by enzyme-linked immunosorbent assay (ELISA). Femur length was measured by B-ultrasound nearest delivery. Neonatal anthropometric indicators were collected from medical records. RESULTS: After adjustment for potential covariates, higher iron (per one standard deviation, SD increase) was detrimentally associated with - 0.22 mm lower femur length, whereas higher transferrin (per one SD increase) was associated with 0.20 mm higher femur length. Compared with normal subjects (10th-90th percentiles), subjects with extremely high (> 90th percentile) iron concentration were detrimentally associated with lower femur length, birth weight, and chest circumference, and a higher risk of low birth weight, LBW (HR: 3.92, 95%CI: 1.28, 12.0). Subjects with high concentration of soluble transferrin receptor, sTFR and transferrin (> 90th percentile) were associated with higher femur length. Subjects with low concentration of iron and ferritin concentrations (< 10th percentile) were associated with a higher risk of LBW (HR: 4.10, 95%CI: 1.17, 14.3) and macrosomia (HR: 2.79, 95%CI: 1.06, 7.35), respectively. CONCLUSIONS: Maternal iron overload in early pregnancy may be detrimentally associated with neonatal anthropometric indicators and adverse birth outcomes.

Associations of early pregnancy serum uric acid levels with risk of gestational diabetes and birth outcomes: a retrospective cohort study.

BACKGROUND: Previous evidence suggests that higher blood uric acid (UA) levels are associated with adverse cardiovascular outcomes during pregnancy and subsequent birth outcomes. However, it has been relatively unclear whether these associations persist in normotensive pregnant women. METHODS: The study was based on a retrospective analysis of 18,250 mother-infant pairs in a large obstetric center in China. Serum UA concentrations in early pregnancy (median: 17.6, IQR: 16.3, 18.6 gestational weeks) were assessed. Hyperuricemia was defined as ≥ one standard deviation (SD) of the reference value for the corresponding gestational age. Outcomes of gestational diabetes mellitus (GDM), preterm birth (PB), low birth weight (LBW), macrosomia, small for gestational age (SGA) and large for gestational age (LGA) were extracted from the medical records. RESULTS: The mean maternal UA level was 0.22 ± 0.05 mmol/L, and 2,896 (15.9%) subjects had hyperuricemia. After adjustment for several covariates, UA was associated with several adverse outcomes. The ORs (95%CI) per one SD increase in serum UA concentration were 1.250 (1.136, 1.277) for GDM, 1.137 (1.060, 1.221) for PB, 1.134 (1.051, 1.223) for LBW, and 1.077 (1.020, 1.137) for SGA, respectively. Similar adverse associations were found between hyperuricemia and GDM, PB (ORs: 1.394 and 1.385, P < 0.001), but not for LBW, macrosomia, SGA, and LGA. Adverse associations tended to be more pronounced in subjects with higher BMI for outcomes including PB, LBW, and SGA (P interaction = 0.001-0.028). CONCLUSION: Higher UA levels in early pregnancy were associated with higher risk of GDM, PB, LBW, and SGA in normotensive Chinese women.

Associations of Dietary Anthocyanidins Intake with Bone Health in Children: A Cross-Sectional Study.

PURPOSE: Bone health and body composition share several common mechanisms like oxidative stress and inflammation. Anthocyanins have antioxidant and anti-inflammatory properties. We have reported that anthocyanins are associated with better body composition in children, but the associations with bone health have not been elucidated. We aimed to explore the association of anthocyanins with bone mineral content (BMC) and bone mineral density (BMD) at multiple sites in children. METHODS: In this cross-sectional study, 452 Chinese children aged 6-9 years were recruited. A validated 79-item food frequency questionnaire was used to collect dietary information. BMC and BMD at multiple sites (whole body; whole body excluding head, WBEH; limbs; arms; legs) were measured by dual-energy X-ray. RESULTS: Higher dietary intake of total anthocyanidins (per one standard deviation increase) was associated with a 1.28-13.6 g (1.31-1.60%, compared to median) higher BMC at all sites and a 3.61-6.96 mg (0.65-0.90%) higher BMD at the whole body, WBEH, and arm sites after controlling for a number of possible covariates. The results were similar and more pronounced for cyanidin, but not for delphinidin and peonidin. Higher dietary intake of cyanidin (per one standard deviation increase) was associated with a 1.33-15.4 g (1.48-1.68%) higher BMC at all sites and a 4.15-7.77 mg (0.66-1.00%) higher BMD at all sites except the legs. No statistically significant associations with BMC or BMD were found for dietary intake of delphinidin and peonidin. CONCLUSIONS: Higher dietary intake of total anthocyanidins and cyanidins were associated with higher BMC and BMD in Chinese children.

Associations of serum concentrations of metal nutrients with postpartum anemia among pregnant Chinese women: A large retrospective cohort study.

Background and Aims: The association between serum concentrations of metal nutrients in pregnancy and postpartum anemia has not been widely studied. This study aimed to determine this association in a large retrospective cohort study. Methods: We included 14,829 Chinese women with singleton pregnancies. Serum concentrations of metals before 28 weeks of gestation, the occurrence of postpartum anemia and other potential covariates were obtained from their laboratory or medical records. Cox regression and restricted cubic spline regression models were used to explore the relationship between serum concentrations of metal nutrients in pregnancy and postpartum anemia. Results: After adjustment for covariates, higher concentrations of iron (Fe), magnesium (Mg) and zinc (Zn) and lower concentrations of copper (Cu) were associated with a lower risk of postpartum anemia. Compared with those whose serum concentrations of metal nutrients were in the bottom quintile (Q1), the hazard ratios (HRs) of those whose serum concentrations of metal nutrients were in the top quintile (Q5) were 0.57 (95% confidence interval (CI): 0.50, 0.64) for Fe, 0.67 (95% CI: 0.60, 0.76) for Mg, 0.82 (95% CI: 0.73, 0.93) for Zn, and 1.44 (95% CI: 1.28, 1.63) for Cu. L-shaped curve relationships were found between increasing concentrations of Fe, Mg, and Zn and incidence of postpartum anemia. Higher serum concentrations of Cu were associated with an increased risk of postpartum anemia. Serum concentrations of Fe in Q5 were associated with a lower risk of postpartum anemia when they coincided with serum concentrations of Mg in Q5, Zn in Q5, or Cu in Q1. Conclusion: Higher serum concentrations of Fe, Mg, and Zn, and lower serum concentrations of Cu were associated with a lower risk of postpartum anemia among pregnant women.

Interaction of n-3 polyunsaturated fatty acids with host CD36 genetic variant for gut microbiome and blood lipids in human cohorts.

BACKGROUND & AIMS: Previous studies suggest an interaction of CD36 genetic variant rs1527483 with n-3 polyunsaturated fatty acids (PUFAs) to modulate blood lipids. However, successful replication is lacking and the role of gut microbiome remains unclear. Here, we aimed to replicate these gene-diet interactions on blood lipids and investigate their possible associations with gut microbiome. METHODS: We evaluated the n-3 PUFA-rs1527483 interaction on blood lipids in two population-based cohorts (n = 4,786). We profiled fecal microbiome and short-chain fatty acids among 1,368 participants. The associations between n-3 PUFAs and bacterial alpha-diversity, taxonomies and short-chain fatty acids by rs1527483 genotypes were analyzed using regression models. RESULTS: CD36 rs1527483-GG carriers responded better to high n-3 PUFA exposure; higher blood HDL-C (beta (95% CI): 0.05 (0.01, 0.08) mmol/L) and lower TG (log-transformed, beta (95% CI): -0.08 (-0.14, -0.02)) were observed among participants whose n-3 PUFA exposure ranked in the top quartile comparing with those in the bottom quartile. We identified docosahexaenoic acid (DHA) as the driven individual n-3 PUFA biomarker, which showed interaction with rs1527483. Among the rs1527483-GG carriers, but not other genotype groups, DHA exposure was positively associated with bacterial Faith's phylogenetic diversity, Observed OTUs, Shannon's diversity index, Dorea, Coriobacteriales Incertae Sedis spp, and fecal propionic acid levels. Another independent longitudinal cohort validated the DHA-rs1527483 interaction on gut microbiome. The identified microbial features were correlated with blood lipids, and the host biosynthesis and metabolism pathways of bile acids and aromatic amino acids. CONCLUSIONS: The present study found that higher n-3 PUFAs were associated with improved blood lipids and gut microbial features only among rs1527483-GG carriers. These findings highlight a potential role of gut microbiome to link the CD36 genetic variant, n-3 PUFAs and blood lipids, revealing a new research direction to interpret the gene-diet interaction for cardiometabolic health.

Associations between thyroid function and gestational diabetes mellitus in Chinese pregnant women: a retrospective cohort study.

BACKGROUND: Thyroid function is known to be closely linked with type 2 diabetes, but data on the association between thyroid function and gestational diabetes mellitus (GDM) are inconsistent. METHODS: A total of 2849 pregnant women were included in this retrospective study. Serum concentrations of thyroid indicators (free tetraiodothyronine, FT4; thyroid-stimulating hormone, TSH; and thyroid peroxidase antibody, TPO Ab) were obtained from a clinical laboratory. The presence of GDM were drawn from medical records. The clinical subtypes of thyroid function (euthyroidism, subclinical hypothyroidism, hyperthyroidism, and isolated hypothyroxinemia) were categorized according to the thresholds of the 2.5th/97.5th and 10th/90th percentiles of TSH and FT4 concentrations. A concentration of > 34 IU/L was defined as indicating TPO Ab-positivity. RESULTS: Two hundred and thirty-five (8.25%) of the 2849 women were TPO Ab-positive. Higher serum concentrations of FT4 (top vs. bottom tertiles) was found to be negatively associated with the risk of GDM. The corresponding odds (OR) values (top tertile vs. bottom tertile) were 0.71 [95% confidence interval (CI): 0.54, 0.93]. No significant associations were observed between the extremely 2.5th/97.5th or 10th/90th percentiles of FT4 concentration, TSH concentration, thyroid function subtypes (vs. euthyroidism), TPO Ab-positivity (vs. -negativity), and the GDM risk. The corresponding results remained similar when TPO Ab-positive subjects were excluded. CONCLUSIONS: A negative association with the risk of GDM was observed for the highest FT4 concentrations tertile. No significant associations were found between the TSH concentration, thyroid function subtypes, TPO Ab positivity, and the GDM risk.

Gut microbiota, inflammation, and molecular signatures of host response to infection.

Gut microbial dysbiosis has been linked to many noncommunicable diseases. However, little is known about specific gut microbiota composition and its correlated metabolites associated with molecular signatures underlying host response to infection. Here, we describe the construction of a proteomic risk score based on 20 blood proteomic biomarkers, which have recently been identified as molecular signatures predicting the progression of the COVID-19. We demonstrate that in our cohort of 990 healthy individuals without infection, this proteomic risk score is positively associated with proinflammatory cytokines mainly among older, but not younger, individuals. We further discover that a core set of gut microbiota can accurately predict the above proteomic biomarkers among 301 individuals using a machine learning model and that these gut microbiota features are highly correlated with proinflammatory cytokines in another independent set of 366 individuals. Fecal metabolomics analysis suggests potential amino acid-related pathways linking gut microbiota to host metabolism and inflammation. Overall, our multi-omics analyses suggest that gut microbiota composition and function are closely related to inflammation and molecular signatures of host response to infection among healthy individuals. These results may provide novel insights into the cross-talk between gut microbiota and host immune system.

The Association of Gut Microbiota With Osteoporosis Is Mediated by Amino Acid Metabolism: Multiomics in a Large Cohort.

CONTEXT: Several small studies have suggested that the gut microbiome might influence osteoporosis, but there is little evidence from human metabolomics studies to explain this association. OBJECTIVE: This study examined the association of gut microbiome dysbiosis with osteoporosis and explored the potential pathways through which this association occurs using fecal and serum metabolomics. METHODS: We analyzed the composition of the gut microbiota by 16S rRNA profiling and bone mineral density using dual-energy X-ray absorptiometry in 1776 community-based adults. Targeted metabolomics in feces (15 categories) and serum (12 categories) were further analyzed in 971 participants using ultra-high-performance liquid chromatography coupled to tandem mass spectrometry. RESULTS: This study showed that osteoporosis was related to the beta diversity, taxonomy, and functional composition of the gut microbiota. The relative abundance of Actinobacillus, Blautia, Oscillospira, Bacteroides, and Phascolarctobacterium was positively associated with osteoporosis. However, Veillonellaceae other, Collinsella, and Ruminococcaceae other were inversely associated with the presence of osteoporosis. The association between microbiota biomarkers and osteoporosis was related to levels of peptidases and transcription machinery in microbial function. Fecal and serum metabolomics analyses suggested that tyrosine and tryptophan metabolism and valine, leucine, and isoleucine degradation were significantly linked to the identified microbiota biomarkers and to osteoporosis, respectively. CONCLUSION: This large population-based study provided robust evidence connecting gut dysbiosis, fecal metabolomics, and serum metabolomics with osteoporosis. Our results suggest that gut dysbiosis and amino acid metabolism could be targets for intervention in osteoporosis.

Early pregnancy vitamin D and the risk of adverse maternal and infant outcomes: a retrospective cohort study.

BACKGROUND: Previous evidence has suggested that lower gestational vitamin D levels might increase the risks of adverse pregnancy and birth outcomes. The results remain inconsistent and require further exploration. METHODS: A total of 2814 Chinese mother-infant pairs were included in this retrospective cohort study. Serum concentrations of 25(OH)D were reviewed in early pregnancy (16.3 ± 2.3 weeks). Outcomes of maternal gestational diabetes mellitus (GDM), cesarean section, fetal distress, preterm birth, low birth weight (LBW), and macrosomia were extracted from the medical records. Cox regression analysis was used to explore these associations. RESULTS: In total, 19.3% of mothers were pregnant at an advanced age (≥35 years), and 40.3% of pregnant women had vitamin D deficiency (< 50 nmol/L). After adjusting for potential covariates, the hazard ratio (HR) (95% CI) per standard deviation (SD) increase of serum 25(OH)D concentrations was 0.86 (0.779, 0.951) for GDM, 0.844 (0.730, 0.976) for preterm birth, and 0.849 (0.726, 0.993) for LBW. Similar protective associations were found for GDM, cesarean section, and preterm birth for a better vitamin D status when compared with vitamin D deficiency. CONCLUSION: Higher early pregnancy vitamin D was associated with a lower risk of GDM, cesarean section, preterm birth, and LBW.

Erythrocyte n-6 Polyunsaturated Fatty Acids, Gut Microbiota, and Incident Type 2 Diabetes: A Prospective Cohort Study.

OBJECTIVE: To examine the association of erythrocyte n-6 polyunsaturated fatty acid (PUFA) biomarkers with incident type 2 diabetes and explore the potential role of gut microbiota in the association. RESEARCH DESIGN AND METHODS: We evaluated 2,731 participants without type 2 diabetes recruited between 2008 and 2013 in the Guangzhou Nutrition and Health Study (Guangzhou, China). Case subjects with type 2 diabetes were identified with clinical and biochemical information collected at follow-up visits. Using stool samples collected during the follow-up in the subset (n = 1,591), 16S rRNA profiling was conducted. Using multivariable-adjusted Poisson or linear regression, we examined associations of erythrocyte n-6 PUFA biomarkers with incident type 2 diabetes and diversity and composition of gut microbiota. RESULTS: Over 6.2 years of follow-up, 276 case subjects with type 2 diabetes were identified (risk 0.10). Higher levels of erythrocyte γ-linolenic acid (GLA), but not linoleic or arachidonic acid, were associated with higher type 2 diabetes incidence. Comparing the top to the bottom quartile groups of GLA levels, relative risk was 1.72 (95% CI 1.21, 2.44) adjusted for potential confounders. Baseline GLA was inversely associated with gut microbial richness and diversity (α-diversity, both P < 0.05) during follow-up and significantly associated with microbiota ß-diversity (P = 0.002). α-Diversity acted as a potential mediator in the association between GLA and type 2 diabetes (P < 0.05). Seven genera (Butyrivibrio, Blautia, Oscillospira, Odoribacter, S24-7 other, Rikenellaceae other, and Clostridiales other) were enriched in quartile 1 of GLA and in participants without type 2 diabetes. CONCLUSIONS: Relative concentrations of erythrocyte GLA were positively associated with incident type 2 diabetes in a Chinese population and also with gut microbial profiles. These results highlight that gut microbiota may play an important role linking n-6 PUFA metabolism and type 2 diabetes etiology.

Erythrocyte Membrane Polyunsaturated Fatty Acids Are Associated with Incidence of Metabolic Syndrome in Middle-Aged and Elderly People-An 8.8-Year Prospective Study.

BACKGROUND: The total and specific types of polyunsaturated fatty acids (PUFAs) related to metabolic syndrome (MetS) remain inconsistent. OBJECTIVE: We assessed the association of erythrocyte n-3 and n-6 PUFAs with MetS and the components of MetS in a cohort population. METHODS: This prospective analysis included 2754 participants (aged 40-75 y) from the Guangzhou Nutrition and Health Study (2008-2019) in China. Erythrocyte PUFAs at baseline were measured using gas chromatography. MetS was assessed every 3 y according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria. Multivariable Cox proportional hazard models were used to evaluate HRs and 95% CIs. RESULTS: We identified 716 incident cases of MetS. The primary analyses showed that the HRs (95% CIs) of MetS (tertile 3 versus 1) were 0.67 (0.56, 0.80) for n-3 PUFAs and 0.70 (0.58, 0.85) for n-6 PUFAs (all Ps trend <0.001). The secondary outcomes showed that, higher erythrocyte very-long-chain (VLC) PUFAs [20:3n-3, docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), arachidonic acid (ARA), and 22:4n-6], but lower α-linolenic acid (ALA) and γ-linolenic acid (GLA), tended to be associated with lower incidences of MetS and its components; among individual MetS components, the associations of PUFAs were more pronounced for hypertriglyceridemia (HTG) and hypertension, followed by low high-density lipoproten (HDL) cholesterol. Significantly higher concentrations of n-3 PUFAs (total, DPA, and DHA) and n-6 PUFAs (total, ARA, and 22:4) were observed in participants with improved (versus progressed) status of MetS (all Ps trend ≤0.003). CONCLUSION: This study reveals that higher erythrocyte VLC n-3 and n-6 PUFAs, but lower 18-carbon PUFAs (ALA and GLA), are associated with lower risks of MetS components (HTG, hypertension, and low HDL cholesterol) and thereby lower MetS incidence in Chinese adults.

Associations Between Maternal Thyroid Function and Birth Outcomes in Chinese Mother-Child Dyads: A Retrospective Cohort Study.

Objective: Although research suggests a close association between maternal thyroid function and birth outcomes, no clear conclusion has been reached. We aimed to explore this potential association in a retrospective cohort study. Methods: This study included 8985 mother-child dyads. The maternal serum free tetraiodothyronine (FT4), thyroid-stimulating hormone (TSH), and thyroid peroxidase antibody (TPO Ab) concentrations and birth outcome data were reviewed from medical records. Subjects with TPO Ab concentrations of >34 and ≤34 IU/ml were classified into the TPO Ab positivity (+) and TPO Ab negativity (-) groups, respectively. Results: Compared with subjects in the normal group (0.1 ≤ TSH < 2.5 mIU/L and TPO Ab-), those with TSH concentrations of 2.5-4.0 mIU/L and TPO Ab- had a 0.65-fold lower risk of low birth weight (LBW). In contrast, those with TSH concentrations of >4.0 mIU/L, regardless of the TPO Ab status, had a 2.01-fold increased risk of LBW. Subclinical hypothyroidism, regardless of the TPO Ab status, was associated with a 1.94-fold higher risk of LBW when compared with that in subjects with euthyroidism and TPO Ab-. No other significant associations were observed. Conclusion: A maternal TSH concentration of 2.5-4.0 mIU/L was associated with a lower risk of LBW when combined with TPO Ab-, whereas subjects with a TSH concentration of >4.0 mIU/L had an increased risk of LBW. Subclinical hypothyroidism appears to be associated with a higher risk of LBW.

Erythrocyte membrane n-3 polyunsaturated fatty acids are inversely associated with the presence and progression of nonalcoholic fatty liver disease in Chinese adults: a prospective study.

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.

Higher serum carotenoids associated with improvement of non-alcoholic fatty liver disease in adults: a prospective study.

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, ß-cryptoxanthin, ß-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% (ß-carotene), 18.2% (α-carotene), 15.6% (ß-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.

Erythrocyte Saturated Fatty Acids and Incident Type 2 Diabetes in Chinese Men and Women: A Prospective Cohort Study.

The association between circulating saturated fatty acids (SFAs) and incident type 2 diabetes (T2D) is reported in Western populations with inconsistent results, while evidence from Asian populations is scarce. We aimed to examine the associations between erythrocyte SFAs and incident T2D in a Chinese population. Between 2008 and 2013, a total of 2683 participants, aged 40⁻75 years, free of diabetes were included in the present analyses. Incident T2D cases were ascertained during follow-up visits. Gas chromatography was used to measure erythrocyte fatty acids at baseline. The Cox proportional hazards model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). During 13,508 person years of follow-up, 216 T2D cases were identified. Compared with the first quartile, multivariable-adjusted HRs (95% CIs) of the fourth quartile were 1.20 (0.82⁻1.76; p = 0.242) for myristic acid (14-carbon tail, zero double bonds; 14:0), 0.69 (0.48⁻0.99; p = 0.080) for palmitic acid (16:0), 1.49 (1.02⁻2.19; p = 0.047) for stearic acid (18:0), 1.46 (1.00⁻2.12; p = 0.035) for arachidic acid (20:0), 1.48 (0.99⁻2.22; p = 0.061) for behenic acid (22:0), and 1.08 (0.74⁻1.56; p = 0.913) for lignoceric acid (24:0). Our findings indicate that individual erythrocyte SFAs are associated with T2D in different directions, with 18:0 and 20:0 SFAs positively associated with the risk, whereas no convincing inverse association for 16:0 SFAs.

Alternate Mediterranean diet score is positively associated with skeletal muscle mass index in middle-aged adults.

Researches have suggested Mediterranean diet might lower the risk of chronic diseases, but data on skeletal muscle mass (SMM) are limited. This community-based cross-sectional study examined the association between the alternate Mediterranean diet score (aMDS) and SMM in 2230 females and 1059 males aged 40-75 years in Guangzhou, China. General information and habitual dietary information were assessed in face-to-face interviews conducted during 2008-2010 and 3 years later. The aMDS was calculated by summing the dichotomous points for the items of higher intakes of whole grain, vegetables, fruits, legumes, nuts, fish and ratio of MUFA:SFA, lower red meat and moderate ethanol consumption. The SMM of the whole body, limbs, arms and legs were measured using dual-energy X-ray absorptiometry during 2011-2013. After adjusting for potential covariates, higher aMDS was positively associated with skeletal muscle mass index (SMI, SMM/height2, kg/m2) at all of the studied sites in males (all P trend<0·05). The multiple covariate-adjusted SMI means were 2·70 % (whole body), 2·65 % (limbs), 2·50 % (arms) and 2·70 % (legs) higher in the high (v. low) category aMDS in males (all P<0·05). In females, the corresponding values were 1·35 % (P trend=0·03), 1·05, 0·52 and 1·20 %, (P trend>0·05). Age-stratified analyses showed that the favourable associations tended to be more pronounced in the younger subjects aged less than the medians of 59·2 and 62·2 years in females and males (P interaction>0·10). In conclusion, the aMDS shows protective associations with SMM in Chinese adults, particularly in male and younger subjects.

Greater Intake of Fruit and Vegetables Is Associated with Greater Bone Mineral Density and Lower Osteoporosis Risk in Middle-Aged and Elderly Adults.

OBJECTIVE: A few studies have suggested that the consumption of fruit and vegetables (FV) may benefit bone health, but limited data are available in Asian subjects. We examined the association between FV intake and bone mineral density (BMD) and osteoporosis in Chinese adults. METHODS: This population-based cross-sectional study involved 2083 women and 1006 men aged 40-75 years in Guangzhou, China. Habitual dietary data was collected from a 79-item food frequency questionnaire by face-to-face interviews. The BMD was measured for the whole body (WB), lumbar spine (LS), total hip (TH) and femur neck (FN) with dual-energy X-ray absorptiometry. RESULTS: After adjustment for potential covariates, we observed dose-dependent associations between total FV intake and BMD and osteoporosis risk. The mean BMD was higher in tertile 3 vs. tertile 1 by 1.33% (TH) and 1.31% (FN) for FV, and 1.10% (WB), 1.57% (TH), and 2.05% (FN) for fruit (all P-trends < 0.05). Significant beneficial associations with BMD at some sites were also found in most fruit categories but not in total vegetables or their subgroups. The odds ratios (95% confidence interval) of osteoporosis (T-score ≤ -2.5) in tertile 3 (vs. 1) were 0.73 (0.58-0.92), 0.37 (0.22-0.60), and 0.71 (0.52-0.97) for FV; 0.82 (0.66-1.03), 0.48 (0.30-0.77) and 0.89 (0.61-1.12) for fruit; and 0.80 (0.64-1.01), 0.57 (0.35-0.92) and 0.76 (0.55-1.05) for vegetables at the LS, TH, and FN, respectively. The favorable association between FV intake and the occurrence of osteoporosis was evident only in subjects with lower BMI (<24.0 kg/m2, P-trends < 0.05). CONCLUSIONS: Greater intake of FV was independently associated with a higher BMD and a lower presence of osteoporosis in middle-aged and elderly Chinese subjects with lower BMI. Fruit tended to have more contribution to the favorable association than vegetables.

Adherence to the Mediterranean diet is associated with a higher BMD in middle-aged and elderly Chinese.

Previous studies showed that better adherence to the Mediterranean diet (MD) is associated with lower risk of chronic diseases, but limited data are available on bone health. We investigated the association of the MD with bone mineral density (BMD) in Chinese adults. We included 2371 participants aged 40-75 years in this community-based cross-sectional study. Dietary information was assessed at baseline and a 3-year follow-up. Alternate Mediterranean diet (aMed) scores were calculated. BMD was determined at the second survey. After adjusting for potential covariates, higher aMed scores were positively and dose-dependently associated with BMD (all P-trends < 0.05). The BMD values were 1.94% (whole body), 3.01% (lumbar spine), 2.80% (total hip), 2.81% (femur neck), 2.62% (trochanter), and 2.85% (intertrochanter) higher in the quintile 5 (highest, vs. quintile 1) aMed scores for all of the subjects (all P-values < 0.05). Similar associations were found after stratifying by gender (P-interaction = 0.338-0.968). After excluding the five non-significant components of vegetables, legumes, fish, monounsaturated to saturated fat ratio, and alcohol intake from the aMed scores, the percentage mean differences were substantially increased by 69.1-150% between the extreme quintiles. In conclusion, increased adherence to the MD shows protective associations with BMD in Chinese adults.

Association of dietary consumption and serum levels of vitamin A and ß-carotene with bone mineral density in Chinese adults.

BACKGROUND: Former studies suggested an adverse effect of hypervitaminosis A on bone health, while the effects of retinol and its precursor (ß-carotene) remain uncertain in populations consuming vitamin A (VA) mainly from plant sources. OBJECTIVE: We investigated the association of serum, dietary retinol, and ß-carotene with bone mineral density (BMD) in Chinese adults. METHODS: We recruited 2101 women and 1053 men (aged 40-75 years) in Guangzhou, China. Dietary intake was assessed through face-to-face interviews with food-frequency questionnaires at baseline and 3 years later. Serum levels of retinol and ß-carotene were determined by HPLC using a baseline specimen, and the BMD for the whole body (WB), lumbar spine (LS), total hip (TH), and femur neck (FN) were measured using dual energy X-ray absorptiometry at follow-up. RESULTS: In general, greater levels of serum retinol, ß-carotene, and the ß-carotene-to-retinol ratio were associated with a higher BMD after adjustment for potential covariates in the total sample. BMD values in the top (vs. bottom) quartile were increased by 2.06% (TH) for retinol; 2.87% (WB), 2.51% (LS), 3.10% (FN) for ß-carotene; 2.21% (WB) and 2.05% (FN) for the ß-carotene-to-retinol ratio in the total sample (all p<0.05). A significant positive association with BMD was observed for dietary intake of ß-carotene and total VA in retinol equivalents at the hip sites in the total sample. CONCLUSION: Higher circulating and dietary levels of VA and ß-carotene and higher serum ß-carotene-to-retinol ratios were positively associated with BMD in Chinese adults consuming relatively low levels of VA, mainly from plant foods.