Yi-xiang Su

Association of natural intake of dietary plant sterols with carotid intima-media thickness and blood lipids in Chinese adults: a cross-section study.

Background Many studies showed a moderate cholesterol-lowering effect of plant sterols (PS), but increased circulating PS might be atherogenic. We evaluated the associations between natural dietary intake of PS and carotid intima–media thickness (IMT) and serum lipids. Methodology/Principal Findings This community-based cross-sectional study included 1160 men and 2780 women aged 31–75 years. Dietary intakes were assessed using a food-frequency questionnaire. The IMTs at the common, bifurcation and internal carotid artery segments, and fasting serum total (TC), LDL (LDLc) and HDL (HDLc) cholesterol, and triglycerides (TG) were determined. After adjusting for potential covariates, multivariate analysis showed a dose-dependent inverse association of total PS intake with serum TC, LDLc, non-HDLc in women (P<0.001) and in men (P<0.05). As compared to the lowest quartile of PS intake (<206 mg/d), the multivariate-adjusted means of TC, LDLc and non-HDLc in the highest quartile of PS intake (447 mg/d) decreased by 5.0%, 6.2% and 6.5% in women (P<0.005), and by 6.4%, 7.1% and 6.7% (P>0.05) in men. Although the IMTs tended to be lower with greater intake of dietary PS, only small differences in the left internal IMT between the highest and lowest groups were observed among men (−7.6%) and women (−5.1%) (P<0.05). The multivariate analysis showed no significant mean differences among the PS groups in HDLc, TG and IMTs at other studied sites among men and women (all P>0.05). Conclusions Greater PS consumption from natural diets is associated with lower serum total, LDL, non-HDL cholesterol and with thinner left internal IMT in women and men.

Validation of an FFQ to estimate the intake of fatty acids using erythrocyte membrane fatty acids and multiple 3d dietary records

OBJECTIVE The estimation of dietary intake in population-based studies is often assessed by the FFQ. The objective of our study is to evaluate the validity of an FFQ used to assess dietary fatty acid intake among middle-aged Chinese adults in Southern China. DESIGN The method of triads was applied to obtain the validity coefficients (VC) of the FFQ for specific fatty acids. A subsample was randomly selected from an earlier cross-sectional study. The FFQ and 3d dietary records were used for dietary assessment, and the fatty acid composition of erythrocyte membranes was determined as the biomarker. RESULTS The Spearman correlation coefficients between the FFQ and 3d dietary records were moderate to good (r = 0.28-0.66). The VC of the FFQ estimated by the method of triads were 0.72, 0.61, 0.65, 0.75 and 0.67 for MUFA, total n-6 fatty acids, alpha-linolenic acid, EPA and DHA, respectively. The VC could not be calculated for SFA, PUFA and total n-3 fatty acids because of negative correlations among the three measurements. But, the correlations between the FFQ and the dietary records were moderate for these fatty acids. CONCLUSIONS Our FFQ applied in Southern Chinese adults was valid to estimate their dietary fatty acid intake and was thus suitable for use in a large cohort study.

Fruit and vegetable intake and bone mass in Chinese adolescents, young and postmenopausal women

OBJECTIVE Previous studies showed an inconsistent association of fruit and vegetable consumption with bone health. We assessed the associations in Chinese adolescents, young and postmenopausal women. DESIGN A cross-sectional study conducted in China during July 2009 to May 2010. SETTING Bone mineral density (BMD) and content (BMC) at the whole body, lumbar spine and left hip were measured with dual-energy X-ray absorptiometry. Dietary intakes were assessed using an FFQ. All these values were separately standardized into Z-scores in each population subgroup. SUBJECTS One hundred and ten boys and 112 girls (11-14 years), 371 young women (20-34 years, postpartum within 2 weeks) and 333 postmenopausal women (50-70 years). RESULTS After adjustment for potential covariates, analysis of covariance showed a significantly positive association between fruit intake and BMD and BMC in all participants combined (P-trend: < 0.001 to 0.002). BMD Z-score increased by 0.25 (or 2.1 % of the mean), 0.22 (3.5 %), 0.23 (3.0 %) and 0.25 (3.5 %), and BMC Z-score increased by 0.33 (5.7 %), 0.25 (5.8 %), 0.34 (5.9 %) and 0.29 (4.7 %), at the total body, lumbar spine, total hip and femoral neck in participants belonging to the top tertile compared with the bottom tertile of fruit intake (all P < 0.05), respectively. There was no significant association between vegetable intake and bone mass at all bone sites studied except for total body BMD (P = 0.030). Relatively more pronounced effects were observed in boys and postmenopausal women. CONCLUSION Our findings add to the existing evidence that fruits and vegetables may have a bone sparing effect.

Association of Weight-Adjusted Body Fat and Fat Distribution with Bone Mineral Density in Middle-Aged Chinese Adults: A Cross-Sectional Study

Background Although it is well established that a higher body weight is protective against osteoporosis, the effects of body fat and fat distribution on bone mineral density (BMD) after adjustment for body weight remains uncertain. Objective To examine the relationship between body fat and fat distribution and BMD beyond its weight-bearing effect in middle-aged Chinese adults. Method The study had a community-based cross-sectional design and involved 1,767 women and 698 men aged 50–75 years. The BMD of the lumbar spine, total hip, and whole body, and the fat mass (FM) and percentage fat mass (%FM) of the total body and segments of the body were measured by dual-energy X-ray absorptiometry. General information on the participants was collected using structured questionnaire interviews. Result After adjusting for potential confounders, an analysis of covariance showed the weight-adjusted (WA-) total FM (or %FM) to be negatively associated with BMD in all of the studied sites (P<0.05) in both women and men. The unfavorable effects of WA-total FM were generally more substantial in men than in women, and the whole body was the most sensitive site related to FM, followed by the total hip and the lumbar spine, in both genders. The mean BMD of the lumbar spine, total hip, and whole body was 3.93%, 3.01%, and 3.65% (in women) and 5.02%, 5.57%, 6.03% (in men) lower in the highest quartile (vs. lowest quartile) according to the WA-total FM (all p<0.05). Similar results were noted among the groups for WA-total FM%. In women, abdominal fat had the most unfavorable association with BMD, whereas in men it was limb fat. Conclusion FM (or %FM) is inversely associated with BMD beyond its weight-bearing effect. Abdominal fat in women and limb fat in men seems to have the greatest effect on BMD.

Daidzein-metabolising phenotypes in relation to serum lipids and uric acid in adults in Guangzhou, China.

Previous studies have suggested that daidzeins metabolites, equol and O-desmethylangolensin (O-DMA), rather than daidzein itself may contribute to the beneficial effects of soya foods in the prevention of CVD. The present study aims to assess the proportion of equol and O-DMA producers, and to compare differences in anthropometric factors, serum lipids, glucose and uric acid between producers and non-producers in Chinese adults aged 20-69 years. For the present cross-sectional study, 202 subjects (100 women and 102 men) were recruited. Twenty-four-hour urinary daidzein and its metabolites were determined in these subjects while on their usual diet and again after a 3-d isoflavone challenge. Fasting serum lipids, glucose and uric acid were examined on their usual diet. Three days of 24 h dietary recalls were used to assess dietary intakes. Of the 202 subjects, 27 (13.4 %) and 27 (13.4 %) excreted equol and O-DMA on their usual diet, and 101 (50 %) and 94 (46.5 %) produced equol and O-DMA after a load of 80 mg/d isoflavones. Equol producers showed lower serum uric acid ( - 10.2 %, P = 0.001), TAG ( - 29.5 %, P = 0.007) and waist:hip ratio ( - 2.6 %, P = 0.032), and tended to have higher HDL cholesterol (6.3 %, P = 0.069) compared with equol non-producers. There were no significant differences in serum lipids, glucose and uric acid between O-DMA producers and non-producers. In conclusion, equol phenotypes might influence cardiovascular risk.

Soya isoflavone consumption in relation to carotid intima–media thickness in Chinese equol excretors aged 40–65 years

Previous studies have suggested that the daidzein metabolite equol rather than daidzein itself contributes to the beneficial effect of soya foods in the prevention of CVD. The aim of the present study is to examine the proportion of equol excretion in Chinese adults and compare plasma lipids and carotid artery intima-media thickness (IMT) between equol excretors and non-excretors, and to evaluate the effect of soya isoflavone intakes on serum lipids and IMT in either equol excretors or non-excretors. Subjects (n 572; women n 362, men n 210) were recruited for the present study. An overnight urine sample was provided by each subject on their usual diet to quantify urinary concentrations of daidzein and equol. Far-wall IMT was determined by B-mode ultrasound in the right carotid at two sites, carotid bulb (CB-IMT) and common carotid artery (CCA-IMT), and fasting serum lipids were measured. Habitual dietary intakes were estimated with a FFQ, and soya isoflavone intake derived from the FFQ was assessed. Of the 572 subjects, the proportion of equol excretors on their usual diet was 25·0 % (n 143). Compared with non-excretors, equol excretors showed significantly lower serum TAG (-38·2 (95 % CI -70·4, -5·9) %, P = 0·012) and CCA-IMT (-4·9 (95 % CI -9·7, -0·3) %, P = 0·033). Equol excretors with higher daily isoflavone intakes (-5·4 mg/d) had significantly lower IMT (-16·2 %, P = 0·035) and tended to have higher HDL-cholesterol (P = 0·055) than did those with lower daily isoflavone intakes (1·5 mg/d), while no association was observed between soya isoflavone intakes and serum lipids or IMT in non-excretors. In conclusion, the benefits of soya isoflavones in preventing CVD may be apparent among equol excretors only.

The validity of the body adiposity index in predicting percentage body fat and cardiovascular risk factors among Chinese

Recent research has suggested that body adiposity index (BAI) correlates more closely with percentage body fat (PBF) than body mass index (BMI). Here, we aimed to evaluate BAIs predictive power for PBF and for obesity‐associated risk factors in the Chinese population.

Erythrocyte membrane n-3 fatty acid levels and carotid atherosclerosis in Chinese men and women

OBJECTIVE Prospective studies have supported the beneficial effects of n-3 fatty acid consumption on cardiac deaths, but limited data focused on atherosclerosis. We investigated the associations between n-3 fatty acids in erythrocytes and atherosclerosis in middle-aged and older Chinese. METHODS 847 subjects (285 men and 562 women), aged 40-65 years, from Guangzhou, China were included in this community-based cross-sectional study between December 2005 and January 2008. The levels of α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in erythrocytes were measured by gas chromatography. Carotid ultrasound examination was conducted to obtain intima-media thickness of the common carotid artery and the carotid bifurcation. Dietary data and other covariates were collected using interviewer-administered questionnaires. RESULTS After adjustment for age, sex, and other confounders, negative dose-response associations between the contents of individual n-3 polyunsaturated fatty acids in the erythrocyte membrane and the prevalence of carotid artery wall thickening and plaque were observed. A comparison in the highest and lowest tertiles gave odds ratios (95% confidence interval) for thickening in the walls of the common carotid artery of 0.58 (0. 34-0.97; P-trend = 0. 037) for DHA, and 0.39 (0.23-0.67; P-trend < 0.001) for ALA. However, EPA was not significantly associated with carotid atherosclerosis. Similar results were found for thickening at the carotid bifurcation and the occurrence of carotid artery plaque. CONCLUSIONS Higher levels of DHA and ALA in the erythrocyte membrane were significantly associated with a lower burden of subclinical atherosclerosis.

Association of Simple Anthropometric Indices and Body Fat with Early Atherosclerosis and Lipid Profiles in Chinese Adults

Objective The discriminatory capability of different adiposity indices for atherosclerosis and lipid abnormalities remains uncertain. This study aimed to identify the best adiposity index for predicting early atherosclerosis and abnormal lipid profiles among anthropometric parameters and body fat measures in middle-aged and elderly Chinese. Method A total of 2,063 women and 814 men (57.6±5.2 y) were recruited for this community-based cross-sectional study. Body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) were assessed. Body fat mass and its percentage values for the whole body and trunk were measured by bioelectrical impedance analysis (BIA). The intima-media thicknesses (IMTs) of the common carotid arteries (CCA), internal carotid arteries (ICA) and bifurcation (BIF) were determined via B-mode ultrasound. The fasting lipid profiles were assessed. Results With per SD increase of adiposity indices, the magnitude of the changes of IMT values and lipid profiles was more substantial for WC, WHR and WHtR in both genders. A multivariate logistic regression analysis indicated that WC, WHR and WHtR were more sensitive in predicting the presence of intima-media thickening at the three segments as well as the lipids disturbances in women and men. In general, BIA-derived measures have no added predictive value for IMT-thickening as opposed to those three traditional abdominal measures. Conclusion Our findings suggest that abdominal anthropometric measures including WC, WHR and WHtR are sensitive for discriminating carotid atherosclerosis and lipids abnormalities. WC is the best index because of its simplicity in routine use.

Biomarkers of dairy fat intake and risk of cardiovascular disease: A systematic review and meta analysis of prospective studies

ABSTRACT Background: Circulating biomarkers of dairy fat provide objective measures of dairy fat intake and facilitate conclusions relevant to populations with different diets and susceptibility to cardiovascular diseases (CVD). Objective: To assess the relationship between circulating pentadecanoic acid (15:0), heptadecanoic acid (17:0) and trans-palmitoleic acid (trans-16:1n-7) and the risk of CVD. Methods: Pubmed, Medline and Embase were searched for prospective cohort studies of the relationship between biomarkers of dairy fat and CVD risk, which included coronary heart disease (CHD), stroke, heart failure and CVD mortality, supplemented by bibliographies of retrieved articles and previous reviews. For each study, relative risks (RR) and 95% confidence intervals (CI) were extracted and pooled with the random effect model. Results: Thirteen studies involving 7,680 CVD cases were included. The pooled RRs of the risk of CVD for the top third vs. bottom third 15:0, 17:0 and trans-16:1n-7 level were 0.94 (95%CI: 0.77–1.15), 0.82 (95% CI: 0.68–0.99) and 0.82 (95% CI: 0.67–1.02), respectively. Subgroup analysis indicated that there were no associations between the concentration of 15:0 with CHD and stroke, but a negative relationship with heart failure (RR = 0.72, 95% CI: 0.55–0.95). Null association was observed between circulating 17:0 and trans-16:1n-7 level and subtypes of CVD except for only one study which reported a negative relationship between 17:0 and heart failure. Conclusion: Higher dairy fat exposure is not associated with an increased risk of CVD.