Wenwen Du

Dynamics of the Chinese diet and the role of urbanicity, 1991-2011.

Chinas food consumption patterns and eating and cooking behaviours changed dramatically between 1991 and 2011. Macronutrient composition has shifted towards fats, and protein and sodium intakes remain high and potassium intake low. The rapid decline in intake of coarse grains and, later, of refined grains and increases in intake of edible oils and animal‐source foods accompanied by major eating and cooking behaviour shifts are leading to what might be characterized as an unhealthy Western type of diet, often based on traditional recipes with major additions and changes. The most popular animal‐source food is pork, and consumption of poultry and eggs is increasing. The changes in cooking and eating styles include a decrease in the proportion of food steamed, baked, or boiled, and an increase in snacking and eating away from home. Prior to the last decade, there was essentially no snacking in China except for hot water or green tea. Most recently, the intake of foods high in added sugar has increased. The dietary shifts are affected greatly by the countrys urbanization. The future, as exemplified by the diet of the three mega cities, promises major growth in consumption of processed foods and beverages.

Dietary patterns and their associations with childhood obesity in China.

Dietary patterns represent the combined effects of foods, and illustrate efficaciously the impact of diet on health outcomes. Some findings of previous studies have limited applicability to Chinese children due to cultural factors. The present study was designed to identify dietary patterns and determine their relationships with obesity among Chinese children and adolescents. Data collected from 1282 children and adolescents aged 7-17 years from the 2011 China Health and Nutrition Survey (CHNS) were used. Dietary patterns were identified using factor analysis of data from three consecutive 24-h dietary recalls. Weight and height were measured following standard methods, and BMI was calculated. Three dietary patterns were identified: modern (high intakes of milk, fast foods and eggs), traditional north (high intakes of wheat, tubers and other cereals) and traditional south (high intakes of vegetables, rice and pork). After adjusting for some confounders and total energy intake, subjects in the highest quartiles of the modern and traditional north patterns were found to have significantly greater risk of obesity (OR 3·10, 95 % CI 1·52, 6·32, and OR 2·42, 95 % CI 1·34, 4·39, respectively). In conclusion, the modern dietary pattern and the traditional north dietary pattern were associated with higher risk of obesity. Promoting healthier eating patterns could help prevent obesity in Chinese children.

Fatty and lean red meat consumption in China: Differential association with Chinese abdominal obesity

AIM We examined the longitudinal association between red meat (RM) consumption and the risk of abdominal obesity in Chinese adults. METHODS AND RESULTS Our data are from 16,822 adults aged 18-75 in the China Health and Nutrition Survey from 1993 to 2011. We assessed RM intake with three 24-h dietary recalls. We defined abdominal obesity as a waist circumference (WC) ≥85 centimeters (cm) for men and ≥80 cm for women. Multilevel mixed-effect regression models showed that men experienced WC increases of 0.74 cm (95% confidence interval [CI]: 0.39-1.09) from a higher total intake of fresh RM and 0.59 cm (95% CI: 0.24-0. 95) from a higher intake of fatty fresh RM but 0.14 cm (95% CI: -0.39 to 0.66) from a higher intake of lean fresh RM in the top quartile versus non-consumers when adjusted for potential confounders. In contrast, after additional adjustment for baseline WC, the odds ratios of abdominal obesity in men were attenuated for total fresh RM (1.25 [95% CI: 1.06-1.47]) and fatty fresh RM (1.22 [95% CI: 1.03-1.44]) but were still not affected by lean fresh RM (0.95 [95% CI: 0.75-1.22]). Women also showed a positive association of fatty fresh RM intake with abdominal obesity. CONCLUSION Greater intake of fatty fresh RM was significantly associated with higher WC (men only) and abdominal obesity risk in Chinese adults. The gender-specific differential association of fatty versus lean fresh RM warrants further study.

Is density of neighbourhood restaurants associated with BMI in rural Chinese adults? A longitudinal study from the China Health and Nutrition Survey

Objectives The neighbourhood availability of restaurants has been linked to the weight status. However, little is known regarding the relation between access to restaurant and obesity among the Chinese population. This study aims to explore the relationship between neighbourhood restaurant density and body mass index (BMI) in rural China. Design A longitudinal study using data from the China Health and Nutrition Survey (CHNS) was conducted. Participants aged 18 and older from the 2004, 2006, 2009 and 2011 CHNS were recruited Separate sex-stratified random intercept-slope growth models of repeated BMI observations were estimated in the study. Setting The data were derived from rural communities in nine provinces in China. Participants There were 11 835 male and 12 561 female person-years assessed in this study. Outcomes The primary outcome of this study was weight status. It is defined as a BMI value, a continuous variable which is calculated by dividing weight (kg) by the square of height (m2). Results The study indicated that among men an increase of one indoor restaurant in the neighbourhood was associated with a 0.01 kg/m2 increase in BMI, and an increase of one fixed outdoor food stall was associated with a 0.01 kg/m2 decrease in BMI, whereas among women, an increase of one indoor restaurant in the neighbourhood was associated with a 0.005 kg/m2 increase in BMI, and an increase of one fast-food restaurant and one fixed outdoor food stall was associated with a 0.02 and 0.004 kg/m2 decline in BMI, respectively. Conclusions The density of neighbourhood restaurants was found to be significantly related to BMI in rural China. The results indicated that providing healthy food choices and developing related public health policies are necessary to tackle obesity among rural Chinese adults.

Change in Body Mass Index and Its Impact on Incidence of Hypertension in 18–65-Year-Old Chinese Adults

Aims: This study assessed change in body mass index (BMI) and its impact on the incidence of hypertension in 18- to 65-year-old Chinese adults. Methods: Two waves of data were collected in 2006 and 2011 by the China Health and Nutrition Survey (CHNS) with samples drawn from nine provinces in China. The logistic regression model was used to examine the association between change in BMI and the incidence of hypertension, and odds ratio (OR) and 95% confident interval (95% CI) were calculated. Results: The risk of incident hypertension increased as the quartile of the BMI difference value (D-value) increased in men (OR and 95% CI for the highest quartile vs. the lowest quartile: 2.303, 1.560–3.401, respectively, p for trend < 0.001) and women (OR and 95% CI for the highest quartile vs. the lowest quartile: 1.745, 1.199–2.540, respectively, p for trend = 0.004). Compared with non-overweight subjects in 2011, the ORs of incident hypertension were all significantly higher for overweight subjects, regardless of their overweight status at baseline (p < 0.05). Conclusions: In conclusion, the results from this study provide unequivocal evidence that prevention of weight gain is likely to have a great impact on the incidence of hypertension in Chinese adults.

Prospective Study of Optimal Obesity Index Cut-Off Values for Predicting Incidence of Hypertension in 18–65-Year-Old Chinese Adults

Background Overweight and obesity increase the risk of elevated blood pressure; most of the studies that serve as a background for the debates on the optimal obesity index cut-off values used cross-sectional samples. The aim of this study was to determine the cut-off values of anthropometric markers for detecting hypertension in Chinese adults with data from prospective cohort. Methods This study determines the best cut-off values for the obesity indices that represent elevated incidence of hypertension in 18–65-year-old Chinese adults using data from the China Health and Nutrition Survey (CHNS) 2006–2011 prospective cohort. Individual body mass index (BMI), waist circumference (WC), waist:hip ratio (WHR) and waist:stature ratio (WSR) were assessed. ROC curves for these obesity indices were plotted to estimate and compare the usefulness of these obesity indices and the corresponding values for the maximum of the Youden indices were considered the optimal cut-off values. Results Five-year cumulative incidences of hypertension were 21.5% (95% CI: 19.4–23.6) in men and 16.5% (95% CI: 14.7–18.2) in women, and there was a significant trend of increased incidence of hypertension with an increase in BMI, WC, WHR or WSR (P for trend < 0.001) in both men and women. The Youden index indicated that the optimal BMI, WC, WHR, WSR cut-off values were 23.53 kg/m2, 83.7 cm, 0.90, and 0.51 among men. The optimal BMI, WC, WHR, WSR cut-off values were 24.25 kg/m2, 79.9 cm, 0.85 and 0.52 among women. Conclusions Our study supported the hypothesis that the cut-off values for BMI and WC that were recently developed by the Working Group on Obesity in China (WGOC), the cut-off values for WHR that were developed by the World Health Organization (WHO), and a global WSR cut-off value of 0.50 may be the appropriate upper limits for Chinese adults.

Association between dietary patterns and blood lipid profiles among Chinese women.

OBJECTIVE The present study aimed to identify dietary patterns and explore their associations with blood lipid profiles among Chinese women. DESIGN In a cross-sectional study, we identified dietary patterns using principal component analysis of data from three consecutive 24 h dietary recalls. The China Health and Nutrition Survey (CHNS) collected blood samples in the morning after an overnight fast and measured total cholesterol (TC), HDL cholesterol (HDL-C), LDL cholesterol (LDL-C) and TAG. SETTING Data were from the 2009 wave of the CHNS. SUBJECTS We studied 2468 women aged 18-80 years from the CHNS. RESULTS We identified three dietary patterns: traditional southern (high intakes of rice, pork and vegetables), snack (high intakes of fruits, eggs and cakes) and Western (high intakes of poultry, fast foods and milk). The traditional southern pattern was inversely associated with HDL-C (β=-0·68; 95 % CI -1·22, -0·14; P<0·05). The snack pattern was significantly associated with higher TAG (β=4·14; 95 % CI 0·44, 7·84; P<0·05). The Western pattern was positively associated with TC (β=2·52; 95 % CI 1·03, 4·02; P<0·01) and LDL-C (β=2·26; 95 % CI 0·86, 3·66; P<0·01). CONCLUSIONS We identified three dietary patterns that are significantly associated with blood lipid profiles. This information is important for developing interventions and policies addressing dyslipidaemia prevention among Chinese women.

Gender difference in the association between food away-from-home consumption and body weight outcomes among Chinese adults

OBJECTIVE The present study aimed to explore the associations between food away-from-home (FAFH) consumption and body weight outcomes among Chinese adults. DESIGN FAFH was defined as food prepared at restaurants and the percentage of energy from FAFH was calculated. Measured BMI and waist circumference (WC) were used as body weight outcomes. Quantile regression models for BMI and WC were performed separately by gender. SETTING Information on demographic, socio-economic, diet and health parameters at individual, household and community levels was collected in twelve provinces of China. SUBJECTS A cross-sectional sample of 7738 non-pregnant individuals aged 18-60 years from the China Health and Nutrition Survey 2011 was analysed. RESULTS For males, quantile regression models showed that percentage of energy from FAFH was associated with an increase in BMI of 0·01, 0·01, 0·01, 0·02, 0·02 and 0·03 kg/m2 at the 5th, 25th, 50th, 75th, 90th and 95th quantile, and an increase in WC of 0·04, 0·06, 0·06, 0·04, 0·06, 0·05 and 0·07 cm at the 5th, 10th, 25th, 50th, 75th, 90th and 95th quantile. For females, percentage of energy from FAFH was associated with 0·01, 0·01, 0·01 and 0·02 kg/m2 increase in BMI at the 10th, 25th, 90th and 95th quantile, and with 0·05, 0·04, 0·03 and 0·03 cm increase in WC at the 5th, 10th, 25th and 75th quantile. CONCLUSIONS Our findings suggest that FAFH consumption is relatively more important for BMI and WC among males rather than females in China. Public health initiatives are needed to encourage Chinese adults to make healthy food choices when eating out.

Relationship between dietary factors and the number of altered metabolic syndrome components in Chinese adults: a cross-sectional study using data from the China Health and Nutrition Survey

Objectives To study the correlation between dietary factors and the number of altered metabolic syndrome components (MetS) in Chinese adults systematically. Setting A cross-sectional study using demographic and dietary data of adults aged 18–75 years from the China Health and Nutrition Survey (2009) was conducted in nine provinces in China. Participants There were 6034 eligible subjects (2800 men and 3234 women) in this study. Outcomes The primary outcome of this study were diet assessments and the number of altered MetS components. Dietary intake was measured using a combination of a 3-day period with 24-hour and household food inventory; average daily intakes of nutrients were estimated according to the Chinese Food Composition Table. Blood samples were analysed in a national central laboratory and the number of clustering MetS components was calculated by adding the presence of each MetS component. Results After adjusting for covariates, and taking zero MetS as comparison, the high risk factors correlating with increased numbers of altered MetS components in men were higher intake of protein (70.4–73.4 g; Ptrend=0.0004), cholesterol (238.7–266.6 mg; Ptrend=0.004), meat (90.6–105.7 g; Ptrend=0.016), fish/seafood (30.4–42.3 g; Ptrend=0.001), and lower intake of coarse cereals (16.5–12.7 g; Ptrend=0.051), tubers (37.3–32.7 g; Ptrend=0.030), and dietary fibre (11.7–11.5 g; ANCOVA p=0.058). Meanwhile, the high risk factors correlating with the increased number of altered MetS components in women were higher intake of wheat (101.9–112.6 g; Ptrend=0.066) and sodium (3862.3–4005.7 mg, Ptrend=0.032), and lower intake of β-carotene (1578.6–1382.7 µg; Ptrend=0.007), milk, and dairy products (17.8–11.5 g; Ptrend=0.002). Conclusions Some foods and nutritional factors correlate with an increased number of altered MetS components in Chinese adults. More prospective, multicentre and clinical research work to further examine these associations is underway.

Food Sources and Potential Determinants of Dietary Vitamin C Intake in Chinese Adults: A Cross-Sectional Study

Vitamin C is essential for human health. It is important to estimate the dietary vitamin C intake in the Chinese population to examine the effects of the nutritional transition occurred in recent decades. The present study aimed to estimate the dietary vitamin C intake in Chinese adults by using cross-sectional data from the 2015 China Nutritional Transition Cohort Study and selecting those aged 18–65 years with complete records of sociodemographic characteristics and dietary measurements (n = 11,357). Wilcoxon rank-sum test, Kruskal-Wallis analysis, Chi-squared test, and multiple logistic regression were employed to analyze the daily dietary vitamin C intake on the basis of three-day 24 h dietary recalls and food sources in relation to demographic factors, to evaluate vitamin C intake status using the estimated average requirement cut-off point, and to explore underlying influencing factors. The mean (SD (standard deviation)) and median (interquartile range) levels of the dietary vitamin C intake in adults were 78.1 (54.6) and 65.4 (61.4) mg/day, respectively. Light vegetables, dark vegetables, fruits, and tubers were the top four food sources, contributing a combined 97.3% of total daily dietary vitamin C intake in the study population. The prevalence of risk of insufficient dietary vitamin C intake was 65.1%. Both the distribution of vitamin C intake and the prevalence of risk of insufficient dietary vitamin C intake differed by several demographic factors. Educational level, residence area, geographic location, vegetable consumption, and total energy intake were independent determinants of the risk of insufficient dietary vitamin C intake. In conclusion, dietary vitamin C intake is inadequate in Chinese adult population, and an increase in vitamin C intake should be recommended especially to the population at risk for vitamin C insufficiency.