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SIGIRR, also known as the single immunoglobulin interleukin-1 receptor (IL-1R)-related molecule, is a member of the IL-1 receptor superfamily and is believed to play a pivotal role in inflammation and anti-inflammatory regulation within the body. Studies have shown that SIGIRR expression is associated with autoimmunity, inflammatory disorders, graft rejection, viral infection, thrombosis and tumour progression. Due to its unique structure and function, SIGIRR is commonly referred to as an ‘orphan receptor’, with IL-37 being the only confirmed ligand molecule for SIGIRR to date. The primary mechanism through which SIGIRR exerts its anti-inflammatory regulatory effect involves the negative modulation of the Toll-like receptor-IL-1R (TLR-IL-1R) signalling pathway. TLR-IL-1R signalling plays critical roles in immune responses triggered by microbial invasion and alterations in the tumour immune microenvironment. This article provides an overview of research findings on SIGIRR as an orphan receptor and its regulatory role in maintaining a delicate balance between natural immune activation and uncontrolled inflammatory processes under pathological conditions.
This study aimed to assess the relationship between COVID-19 infection-related conditions and depressive symptoms among medical staff after easing the zero-COVID policy in China, and to further examine the mediating role of professional burnout.
Methods
A total of 1716 medical staff from all levels of health care institutions in 16 administrative districts of Beijing, China, were recruited to participate at the end of 2022 in this cross-sectional study. Several multiple linear regressions and mediating effects tests were performed to analyze the data.
Results
At the beginning of the end of the zero-COVID policy in China, 91.84% of respondents reported infection with COVID-19. After adjusting for potential confounding variables, the severity of infection symptoms was significantly positively associated with high levels of depressive symptoms (β = 0.06, P < 0.001), and this association was partially mediated by professional burnout. Specifically, emotional exhaustion (95% CI, 0.131, 0.251) and depersonalization (95% CI, 0.009, 0.043) significantly mediated the association between the severity of infection symptoms and depressive symptoms.
Conclusions
The mental health of medical staff with more severe symptoms of COVID-19 infection should be closely monitored. Also, interventions aimed at reducing emotional exhaustion and depersonalization may effectively reduce their risk of developing depressive symptoms.
To be successfully used in daily life situations, exoskeletons should be effective across multimodal scenarios, including walking on various terrains, and transitions between locomotion modes such as walking-to-stop. Correct continuous gait phase estimation is essential for high-level walking assistance control. Despite the impressive advances in gait phase estimation for a variety of locomotion modes, transition gait phase estimation is rarely researched, leading to the jittering of exoskeletons during walking-to-stop transitions. We propose an optimized phase oscillator (PO-opt) that estimates the gait phase correctly during transition gaits in multimodal locomotion, which is beneficial to eliminating the jittering. In the phase plane, a lateral axis extreme difference (LAED) is adopted to classify transition gaits. The threshold of LAED for transition gaits in multimodal locomotion was preliminarily determined by simulation, which was then applied and validated in experiments. Simulation results indicated that a threshold of 15.0 was suitable for transition gaits classification during treadmill walking, free walking, and ramp ascent/descent, while results of the experiment showed that a threshold between 6.5 and 10.5 was applicable for treadmill walking, free walking, and stair ascent/descent. In particular, the jittering elimination rates for 3, 4, and 5 km/h treadmill walking were improved from 29%, 21%, and 4% (PO model) to 100%, respectively, when the threshold of LAED was set at 15.0 in PO-opt model. The results indicated a significant increase in the rate of jittering elimination when the PO-opt model was applied. The model holds great promise in real-world applications for prostheses and other types of exoskeletons.
Arising of disasters by climate change had affected crop growth and yield, and then threaten local to global food security, particularly heat stress. Therefore, hazard assessment is essential to develop effective disaster risk management and adaptation interventions to ensure food security. In this study, the accumulated heat stress days (DAY), heat stress intensity (HSI) and heat degree-days (HDD) during the post-silking period of summer maize in The Huang-Huai-Hai Plain were investigated. Based on the optimal probability distribution function of HDD and information diffusion theory, we compute heat stress classification index and the possibility of heat stress, respectively. During 1981–2019, DAY, HSI and HDD were 11.8 d, 31.9°C and 23.6°Cd and increased by 0.67 d/decade, 0.10°C/decade and 3.14°Cd/decade, respectively. The threshold and hazard probability of mild, moderate and severe heat stress were 9.4, 19.4 and 34.2°Cd and 16.6, 9.3 and 4.5%, respectively. The heat stress hazard index (M) was 0.48, ranged from 0 to 0.77 during 1981 to 2019. M will increase in the future at all regions, particularly after 2060. Under SSP5-8.5 climate scenario, M ranged from 0.95 to 1.20 in 2080s, about two times than historical period. This could be used in optimizing agricultural management in summer maize production in order to combat heat stress under projected climate change.
There is still controversy about optimal dietary iodine intake as the Universal Salt Iodization policy enforcement in China. A modified iodine balance study was thus conducted to explore the suitable iodine intake in Chinese adult males using the iodine overflow hypothesis. In this study, thirty-eight apparently healthy males (19·1 (sd 0·6) years) were recruited and provided with designed diets. After the 14-d iodine depletion, daily iodine intake gradually increased in the 30-d iodine supplementation, consisting of six stages and each of 5 d. All foods and excreta (urine, faeces) were collected to examine daily iodine intake, iodine excretion and the changes of iodine increment in relation to those values at stage 1. The dose–response associations of iodine intake increment with excretion increment were fitted by the mixed effects models, as well as with retention increment. Daily iodine intake and excretion were 16·3 and 54·3 μg/d at stage 1, and iodine intake increment increased from 11·2 μg/d at stage 2 to 118·0 μg/d at stage 6, while excretion increment elevated from 21·5 to 95·0 μg/d. A zero iodine balance was dynamically achieved as 48·0 μg/d of iodine intake. The estimated average requirement and recommended nutrient intake were severally 48·0 and 67·2 μg/d, which could be corresponded to a daily iodine intake of 0·74 and 1·04 μg/kg per d. The results of our study indicate that roughly half of current iodine intakes recommendation could be enough in Chinese adult males, which would be beneficial for the revision of dietary reference intakes.
This article documents novel large-sample evidence on the informational role of interfirm ownership networks in bank lending. Using comprehensive loan-level data in China, we find that banks’ internal loan ratings at issuance predict subsequent delinquent events more accurately when borrowers are connected to banks’ existing customers via ownership networks. In post-issuance monitoring for delinquent loans, banks with access to ownership networks manage to downgrade their initial ratings before late payments. These findings suggest that ownership networks facilitate the transmission of private information for bank lending. Moreover, ownership networks are more important for transmitting information related to small and medium enterprises.
Data on average iodine requirements for the Chinese population are limited following implementation of long-term universal salt iodisation. We explored the minimum iodine requirements of young adults in China using a balance experiment and the ‘iodine overflow’ hypothesis proposed by our team. Sixty healthy young adults were enrolled to consume a sequential experimental diet containing low, medium and high levels of iodine (about 20, 40 and 60 μg/d, respectively). Each dose was consumed for 4 d, and daily iodine intake, excretion and retention were assessed. All participants were in negative iodine balance throughout the study. Iodine intake, excretion and retention differed among the three iodine levels (P < 0·01 for all groups). The zero-iodine balance derived from a random effect model indicated a mean iodine intake of 102 μg/d, but poor correlation coefficients between observed and predicted iodine excretion (r 0·538 for μg/d data) and retention (r 0·304 for μg/d data). As iodine intake increased from medium to high, all of the increased iodine was excreted (‘overflow’) through urine and faeces by males, and 89·5 % was excreted by females. Although the high iodine level (63·4 μg/d) might be adequate in males, the corresponding level of 61·6 μg/d in females did not meet optimal requirements. Our findings indicate that a daily iodine intake of approximately half the current recommended nutrient intake (120 μg/d) may satisfy the minimum iodine requirements of young male adults in China, while a similar level is insufficient for females based on the ‘iodine overflow’ hypothesis.
The early Cambrian Carinachitidae, a family in the subclass Conulata, are intriguing and important small shelly fossils. Their gently tapering, tube-shaped skeletons consist of convex faces separated from each other by broad, deep corner sulci, and they exhibit triradial, pentaradial, or predominantly tetraradial symmetry. However, the morphology of the aperture and the modes of growth of carinachitid skeletons as well as the anatomy of their soft parts are unknown. Examination of a single new, exceptionally well-preserved specimen of tetramerous Carinachites spinatus Qian, 1977, collected from the lower Cambrian Kuanchuanpu Formation in South China, reveals: (1) that its aperture is connected to a small mass of relic soft tissue and (2) that the apertural end of each of the four faces is developed into a subtriangular lappet or oral lobe that is smoothly folded toward the long axis of the tube, partially closing the tube aperture. Similarities between thorn-like spines on the faces and the oral lobes indicate that the transverse ribs were periodically displaced from the perradial portion of the aperture during formation of new ribs. In addition, the tube walls may have undergone secondary thickening during growth. The growth pattern of the tube and the spatial relationships between the tube aperture and soft parts are analogous to those of co-occurring olivooids. These findings further strengthen the previously proposed hypothesis that coeval carinachitids, olivooids, hexangulaconulariids, and Paleozoic conulariids are closely related taxa within the subphylum Medusozoa. Finally, carinachitids most likely represent an evolutionary intermediate between olivooids and hexangulaconulariids.
The earliest fossil record of animal biomineralization occurs in the latest Ediacaran Period (c. 550 Ma). Cloudina and Sinotubulites are two important tubular taxa among these earliest skeletal fossils. The evolutionary fate of Cloudina-type fossils across the Ediacaran–Cambrian transition, however, remains poorly understood. Here we report a multi-layered tubular microfossil Feiyanella manica gen. et sp. nov. from a phosphorite interval of the lowest Cambrian Kuanchuanpu Formation, southern Shaanxi Province, South China. This newly discovered fossil is a conical tube with a ‘funnel-in-funnel’ construction, showing profound morphological similarities to Cloudina and Conotubus. On the other hand, the outer few layers, and particularly the outermost layer, of Feiyanella tubes are regularly to irregularly corrugated, a feature strikingly similar to the variably folded/wrinkled tube walls of Sinotubulites. The Feiyanella tubes additionally exhibit two orders of dichotomous branching, similar to branching structures reported occasionally in Cloudina and possibly indicative of asexual reproduction. Owing to broad similarities in tube morphology, tube wall construction and features presumably indicative of asexual reproduction, Cloudina, Conotubus, Sinotubulites and the here described Feiyanella may thus constitute a monophyletic group traversing the Ediacaran–Cambrian boundary. The tube construction and palaeoecological strategy of Feiyanella putatively indicate evolutionary continuity in morphology and palaeoecology of benthic metazoan communities across the Ediacaran–Cambrian transition.
The objective of the present paper was to review the consumption status of meat and dairy products among Chinese residents. The research topics included production, consumption and health implications of dairy and meat, and the data sources included reports of national surveys, research papers and data from the National Bureau of Statistics of China. The average intake of meat, especially pork, has continued to increase in China. Pork intake increased from 37·1 g/d in 1992 to 64·3 g/d in 2012. There was a much higher margin in rural regions; pork intake of rural residents increased from 25·0 g/d in 1992 to 59·9 g/d in 2012, which resulted in a narrowed gap between urban and rural areas. Although the average intake of dairy products increased from 14·9 g/d in 1992 to 24·7 g/d in 2012, the overall level was still lower. There was a significant difference of dairy consumption between urban and rural residents. The gap of per capita consumption of milk between urban and rural households was 3·5 kg/year in 1990, reached the maximum of 16·9 kg/year in 2003, then decreased to 8·7 kg/year in 2012. In conclusion, the finding of this review sheds light on some problems with food consumption patterns in China. Effective strategies need to be adopted in order to change the consumption patterns. The consumption of milk and replacing pork with poultry or fish or other health foods should be encouraged.
To evaluate vitamin D deficiency prevalence and risk factors among pregnant Chinese women.
Design
A descriptive cross-sectional analysis.
Setting
China National Nutrition and Health Survey (CNNHS) 2010–2013.
Subjects
A total of 1985 healthy pregnant women participated. Possible predictors of vitamin D deficiency were evaluated via multiple logistic regression analyses.
Results
The median serum 25-hydroxyvitamin D level was 15·5 (interquartile range 11·9–20·0, range 3·0–51·5) ng/ml, with 74·9 (95 % CI 73·0, 76·7) % of participants being vitamin D deficient (25-hydroxyvitamin D <20 ng/ml). According to the multivariate logistic regression analyses, vitamin D deficiency was positively correlated with Hui ethnicity (P=0·016), lack of vitamin D supplement use (P=0·021) and low ambient UVB level (P<0·001). In the autumn months, vitamin D deficiency was related to Hui ethnicity (P=0·012) and low ambient UVB level (P<0·001). In the winter months, vitamin D deficiency was correlated with younger age (P=0·050), later gestational age (P=0·035), higher pre-pregnancy BMI (P=0·019), low ambient UVB level (P<0·001) and lack of vitamin D supplement use (P=0·007).
Conclusions
Vitamin D deficiency is prevalent among pregnant Chinese women. Residing in areas with low ambient UVB levels increases the risk of vitamin D deficiency, especially for women experiencing advanced stages of gestation, for younger pregnant women and for women of Hui ethnicity; therefore, vitamin D supplementation and sensible sun exposure should be encouraged, especially in the winter months. Further studies must determine optimal vitamin D intake and sun exposure levels for maintaining sufficient vitamin D levels in pregnant Chinese women.
To investigate the effect of different feeding patterns on the occurrence of diseases among infants.
Design
Data on socio-economic status, feeding patterns before 6 months (exclusive breast-feeding (EBF); mixed feeding with breast milk and formula (MBF); exclusive formula-feeding (EFF)) and illness of infants were collected via face-to-face interviews. The proportions of infants who had ever been ill or hospitalized and their potential influence factors were investigated.
Setting
Eight large cities in China.
Subjects
Infants (n 1654) aged 0–11·9 months were recruited from hospitals.
Results
For infants aged 0–2·9 months, the percentage who had been ill was 19·2 %, 24·1 % and 26·3 % among the EBF, MBF and EFF groups, respectively. For those aged 3–5·9 and 6–11·9 months, the corresponding percentages were 41·6 %, 45·6 % and 51·0 %, and 67·0 %, 73·4 % and 67·7 %. Respiratory disease was the most common reported illness and cause of hospitalization. The risks of having (total) illness, diarrhoea and respiratory disease increased significantly with age, but not allergic disease. Compared with EBF, MBF and EFF infants had significantly higher risks of having illnesses except for allergic disease, and feeding patterns were not related to hospitalization. Low birth weight, middle family income and low level of mother’s education also increased the risk of illness.
Conclusions
A protective effect of EBF against total illness in urban Chinese infants was found. An increasing trend with age was observed among the percentages of infants who had been ill or had diarrhoea or respiratory disease, but not allergic disease.
The feasibility of an accelerated test method on revealing the high cycle fatigue (HCF) limit stresses of a near alpha titanium alloy was successfully verified firstly during the rotary bending tests. The stress-controlled low cycle fatigue (LCF) tests at room temperature were then carried out over a range of maximum stresses and stress ratios to reveal the basic LCF strength. Finally, the core emphasis was focused on the influences of the predamage from LCF loadings on the subsequent HCF limit stresses corresponding to the life of 106 cycles. A total of eight levels of predamage from LCF with different stress levels, stress ratios, and proportions of LCF life were introduced, which resulted in obvious deterioration of the HCF stress limits (even under only 2% of expected LCF life). The fracture analysis exhibited that there were typical LCF failure characteristics in crack initiation regions of specimens under prior LCF loadings.
To investigate the association of regional fat depots with metabolic risk factors in Chinese women.
Design
Total and regional fat depots including android fat and gynoid fat were measured by dual-energy X-ray absorptiometry. Central fat distribution was defined as android:gynoid fat ratio. Metabolic risk factors were defined as elevated TAG, reduced HDL-cholesterol, elevated blood pressure and elevated fasting plasma glucose. Logistic regression analyses were performed to examine the associations of regional fat depots with metabolic risk factors. The odds ratios of metabolic risks were further calculated according to tertiles of android fat and gynoid fat.
Setting
Participants were recruited from a community-based cross-sectional study. Face-to-face questionnaires, anthropometric and dual-energy X-ray absorptiometry measures were conducted.
Subjects
Chinese women (n 609) aged 18–79 years.
Results
Android fat and android:gynoid fat ratio were associated with significantly increased odds (OR = 1·4–3·7; P < 0·01) for almost all risk factors, whereas gynoid fat was independently associated with significantly decreased odds (OR = 0·3–0·6; P < 0·01). The inverse associations of gynoid fat with metabolic risk factors remained after adjusting for android fat. Even if their android fat level was in high, women in the highest tertile of gynoid fat had lower odds of having at least two metabolic risk factors compared with women in the lowest gynoid fat tertile (P for trend < 0·01).
Conclusions
There were opposite associations of android and gynoid fat with metabolic risks in Chinese women. Gynoid fat rather than android fat might be a more important inclusion in metabolic disease risk evaluation in female Asians.
Both stunting and overweight are present in children across China. Seemingly paradoxical, these two conditions can also coexist in the same child. The aim was to examine the associations between dietary food/nutrient intake and plasma lipid profiles related to stunting and overweight status.
Design
The 2002 China National Nutrition and Health Survey was a family-based nationally representative cross-sectional study.
Setting
Thirty-one provinces, autonomous regions and municipalities.
Subjects
The study included 13 770 children aged 2–17 years. The sample size for the four exposure groups was 10 814 for children of normal height and weight, 2128 for stunted, 729 for overweight and 99 for stunted overweight.
Results
Compared with children of normal height and weight, stunted and stunted overweight children consumed more high-energy-dense foods with a lower dietary diversity score, less protein, polyunsaturated fat and Fe, and a higher molar ratio of phytate to Ca. On the contrary, overweight children tended to consume significantly less carbohydrates and more protein and fat. Overall, stunted overweight children consumed lower amounts of vegetables, fruit, white meat (poultry and fish) and more milk. The OR for prevalent dyslipidaemia were 1·32 (95 % CI 1·13, 1·53), 1·76 (95 % CI 1·48, 2·09) and 2·59 (95 % CI 1·65, 4·07) among stunted, overweight and stunted overweight children, respectively, compared with children of normal height and weight. In addition, being overweight was significantly associated with high glucose concentrations, whereas stunting was significantly associated with having anaemia.
Conclusions
Limited dietary diversity and intake of high-energy-dense foods were notably observed among stunted overweight children. Furthermore, being stunted and/or overweight was associated with an increased likelihood of unhealthy lipid profiles.
The objective of the present study is to measure basal energy expenditure (BEE) using the Cosmed K4b2 portable metabolic system (Rome, Italy) and to develop a new predictive equation for BEE in southern Chinese adults. A total of 165 healthy Chinese adults aged 18–45 years with normal body weight were involved in the present study. BEE was measured by Cosmed K4b2. Body composition was determined by body composition analysers (ImpediMed DF50, QLD, Australia). Multiple linear regression analysis and correlation analysis were applied to develop a new optimal equation for predicting BEE of southern healthy Chinese adults. Measured BEE (mBEE) of southern Chinese healthy adults was 5513 (sem 96) kJ/d, which was similar to the results predicted by the equation developed by of Liu 5579 (sem 57) kJ/d (P = 0·37) and significantly lower than those from equations developed by Henry (5763 (sem 54) kJ/d), Schofield (5898 (sem 58) kJ/d) and Harris–Benedict (HB; 5863 (sem 51) kJ/d) (all P = 0·001). The optimal equation developed by our data was BEE (kJ/d) = 277+89 weight (kg)+600 sex (male = 1 and female = 0) (r2 = 0·48, n 165). For males, BEE (kJ/d) = 105 weight (kg) − 58 (r2 = 0·27, n 79); for females, BEE (kJ/d) = 69 weight (kg)+1335 (r2 = 0·24, n 86). In conclusion, the mBEE of southern Chinese healthy adults was 5513 (sem 96) kJ/d. The BMR of Chinese adults of normal weight is overestimated by widely used prediction equations developed by Henry, Schofield and HB. The equation developed in the present study (equation 7) can be used in predicting BEE for Chinese adults aged 18–45 years with normal body weight.
To assess the association of indicators of general and abdominal obesity with the prevalence of type 2 diabetes (T2DM) and intermediate hyperglycaemia (IHG) in the Chinese population.
Methods
We used data of 50 905 adults aged 18–79 years in the 2002 China National Nutrition and Health Survey. Recommended Chinese cut-off values were used for BMI (24 kg/m2) and waist circumference (WC; 85 cm in men, 80 cm in women). Optimal cut-offs for waist:height ratio (WHtR) were determined from analyses of receiver-operating characteristic (ROC) curves.
Results
The prevalence of T2DM and IHG was 2·6 % and 1·9 % respectively. ROC curve analyses indicated 0·5 as the optimal cut-off value for WHtR in both sexes. High BMI, WC and WHtR were all associated with the prevalence of glucose tolerance abnormalities, with the highest prevalence ratio (PR) for high WHtR (men: PR = 2·85, 95 % CI 2·54, 3·21; women: PR = 3·10, 95 % CI 2·74, 3·51). When combining BMI and WHtR, in men either a high BMI or a high WHtR alone was associated with increased risk. Among women, a high BMI without a concomitant high WHtR was not associated with increased glucose tolerance abnormalities risk, whereas a high WHtR was associated with risk irrespective of BMI.
Conclusions
Among the Chinese adult population measures of central obesity are better predictors of glucose tolerance abnormalities prevalence than BMI. A WHtR cut-off point of 0·5 for both men and women can be considered as optimum for predicting (pre-) diabetes and may be a useful tool for screening and health education.
China is experiencing a rapid increase in overweight and related conditions. This study describes the geographic variation in BMI levels and the prevalence of overweight and underweight in Chinese adults, and assesses their relations with regional Gross Domestic Product (GDP) per capita levels. BMI values and the prevalence of overweight and underweight in 143 522 adults from the Chinese National Nutrition and Health Survey (2002) were calculated according to geographic regions in China. Their correlations with GDP were assessed. Linear and logistic regressions were used to adjust for age, sex and city–country composition. BMI and the prevalence of overweight were highest in the Bohai coastal regions while lowest in southern provinces such as Guangdong, Guangxi, Yunnan, Hunan and Fujian. Mean BMI values ranged from 20·72 to 25·48 kg/m2, and the prevalence of overweight ranged from 6·6 to 53·9 %. BMI and the prevalence of overweight were positively correlated with economic development, particularly in the northern regions. However, for regions with similar GDP per capita levels, those in the south had substantially lower BMI and lower prevalence of overweight than those in the north. Interestingly, some southern regions with high GDP per capita had low BMI and low prevalence of overweight. The prevalence of underweight was highest in the south. Substantial geographic variations in the prevalence of overweight and underweight exist in China. Such variations cannot be fully explained by the differences in economic status. China is currently facing challenges of both overweight and underweight but priorities vary in different regions.
In order to prioritise interventions for micronutrient deficiencies in China, the populations affected by iron and zinc deficiencies were assessed based on data from the 2002 China National Nutrition and Health Survey. The costs and cost-effectiveness of supplementation, food diversification and food fortification were estimated using the standard World Health Organization ingredients approach. Results indicated that 30% of children (<2 years), adults (>60 years), pregnant and lactating women, and 20% of women of reproductive age were anaemic, some 245 million people. Approximately 100 million people were affected by zinc deficiency (zinc intake inadequacy and stunting), the majority living in rural areas. Among interventions on iron and zinc deficiency, biofortification showed the lowest costs per capita, I$0.01 (international dollars), while dietary diversification through health education represented the highest costs at I$1148. The cost-effectiveness of supplementation, food fortification and dietary diversification for iron deficiency alone was I$179, I$66 and I$103 per disability-adjusted life-year (DALY), respectively. Data for biofortification were not available. For zinc deficiency, the corresponding figures were I$399, I$153 and I$103 per DALY, respectively. In conclusion, iron and zinc deficiencies are of great public health concern in China. Of the two long-term intervention strategies, i.e. dietary diversification and biofortification with improved varieties, the latter is especially feasible and cost-effective for rural populations. Supplementation and fortification can be used as short-term strategies for specific groups.
To assess the intake inadequacy and food sources of zinc of people in China.
Design and subjects
Diets of 68 962 subjects aged 2–101 years (urban 21 103, rural 47 859) in the 2002 China National Nutrition and Health Survey were analysed. Dietary intake was assessed using 24-hour recall for three consecutive days. Zinc intake inadequacy was calculated based on values suggested by the World Health Organization.
Results
The median zinc intake ranged from 4.9 mg day− 1 (urban girls, 2–3 years) to 11.9 mg day− 1 (rural males, 19+ years). The zinc density of urban residents (2–3 to 19+ years) was 5.0–5.3 mg day− 1 (1000 kcal)− 1, significantly higher than that of their rural counterparts (4.7–4.8 mg day− 1 (1000 kcal)− 1). Differences in food sources of zinc from cereal grains (27.4–45.1 vs. 51.6–63.2%) and animal foods (28.4–54.8 vs. 16.8–30.6%) were found between urban and rural residents. Zinc from vegetables and fruits (8.2–13.8 vs. 9.7–12.4%) and legumes (1.3–3.3 vs. 2.5–3.4%) was comparable between urban and rural residents. The proportion of zinc intake inadequacy ranged between 2.8% (urban females, 19+ years) and 29.4% (rural lactating women). Rural residents had higher proportions of zinc intake inadequacy than their urban counterparts. Significantly higher proportions of zinc inadequacy were found in the category of phytate/zinc molar ratio >15 for both rural and urban residents.
Conclusions
About 20% of rural children are at risk of inadequate zinc intake, with phytate as a potential important inhibitor. Moreover, lactating women are also considered a vulnerable group.