Joint association of magnesium and iron intake with anemia among Chinese adults

Identification and prediction of association patterns between nutrient intake and anemia using machine learning techniques: results from a cross-sectional study with university female students from Palestine

PURPOSE

This study utilized data mining and machine learning (ML) techniques to identify new patterns and classifications of the associations between nutrient intake and anemia among university students.

METHODS

We employed K-means clustering analysis algorithm and Decision Tree (DT) technique to identify the association between anemia and vitamin and mineral intakes. We normalized and balanced the data based on anemia weighted clusters for improving ML models' accuracy. In addition, t-tests and Analysis of Variance (ANOVA) were performed to identify significant differences between the clusters. We evaluated the models on a balanced dataset of 755 female participants from the Hebron district in Palestine.

RESULTS

Our study found that 34.8% of the participants were anemic. The intake of various micronutrients (i.e., folate, Vit A, B5, B6, B12, C, E, Ca, Fe, and Mg) was below RDA/AI values, which indicated an overall unbalanced malnutrition in the present cohort. Anemia was significantly associated with intakes of energy, protein, fat, Vit B1, B5, B6, C, Mg, Cu and Zn. On the other hand, intakes of protein, Vit B2, B5, B6, C, E, choline, folate, phosphorus, Mn and Zn were significantly lower in anemic than in non-anemic subjects. DT classification models for vitamins and minerals (accuracy rate: 82.1%) identified an inverse association between intakes of Vit B2, B3, B5, B6, B12, E, folate, Zn, Mg, Fe and Mn and prevalence of anemia.

CONCLUSIONS

Besides the nutrients commonly known to be linked to anemia-like folate, Vit B6, C, B12, or Fe-the cluster analyses in the present cohort of young female university students have also found choline, Vit E, B2, Zn, Mg, Mn, and phosphorus as additional nutrients that might relate to the development of anemia. Further research is needed to elucidate if the intake of these nutrients might influence the risk of anemia.

Iron Metabolism, Calcium, Magnesium and Trace Elements: A Review

Iron (Fe) is fundamental to life on earth. In the human body, it is both essential and harmful if above threshold. A similar balance applies to other elements: calcium (Ca), magnesium (Mg), and trace elements including copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), mercury (Hg), and nickel (Ni). These elements share some proteins involved in the absorption and transport of Fe. Cu and Cd can inhibit Fe absorption, while excess of Fe may antagonize Cu metabolism and reduce ceruloplasmin (Cp). Excessive Fe can hinder Zn absorption and transferrin (Trf) can bind to both Zn and Ni. Ca is able to inhibit the divalent metal transporter 1 (DMT1) in a dose-dependent manner to reduce Fe absorption and low Mg concentrations can exacerbate Fe deficiency. Pb competitively inhibits Fe distribution and elevated Cd absorption reduces Fe uptake. Exposure to Hg is associated with higher ferritin concentrations and Ni alters intracellular Fe metabolism. Fe removal by phlebotomy in hemochromatosis patients has shown to increase the levels of Cd and Pb and alter the concentrations of trace elements in some types of anemia. Yet, the effects of chronic exposure of most trace elements remain poorly understood.

Role of mineral nutrients other than iron in pregnancy: under recognized opportunities to improve maternal/fetal outcomes: a literature review

BACKGROUND

Anemia during pregnancy is an important global health concern, affecting 40% of women worldwide, and iron deficiency shares a significant proportion of the burden. From conception to birth, pregnancy is a period when women undergo metabolic and physiological changes. The nutritional needs are higher during pregnancy; thus, adequate nutrition is essential to maintain fetal growth and development. However, adverse effects due to deficiency in nutrition during pregnancy can result in maternal, fetal and neonatal complications. Despite the multifactorial etiology of anemia, iron deficiency is assumed as the primary cause of anemia during pregnancy and hence, mitigation strategy pivots around it for anemia management. Therefore, excluding other contributors, a single-micronutrient approach with iron supplements remains a myopic approach and this can exacerbate iron deficiency anemia. Micronutrient deficiencies are of particular concern as they may pose a silent threat to the survival and well-being of reproductive-age women and their infants.

AIM

Micronutrients, especially trace minerals, play a myriad of roles in pregnancy, and the lack of each one causes adverse complications to both the mother and the fetus. In this review paper, we attempt to piece together available information regarding the adverse effects of abnormal trace mineral levels along with iron deficiency on the mother and the fetus.

METHOD

A non-systematic literature search in PubMed, Google Scholar, and the Cochrane databases, for publications on minerals and vitamins during pregnancy and the possible influence of supplements on pregnancy outcomes.

CONCLUSION

Micronutrient deficiency exacerbates the pregnancy-induced anemia and other adverse birth outcomes. Micronutrient supplementation during pregnancy can combat anemia as well as reduce a number of adverse pregnancy outcomes in a comprehensive manner.

The association between serum magnesium and chronic kidney disease in Chinese adults: a cross-sectional study

BACKGROUND

Magnesium (Mg) is both an essential macro-element and a known catalyst, and it plays a vital role in various physiological activities and mechanisms in relation to chronic kidney disease (CKD). However, epidemiological evidence involving this is limited and not entirely consistent. This study aims to explore the association of serum Mg concentrations with the risk of CKD among general Chinese adults.

METHODS

A total of 8,277 Chinese adults were included in the wave of 2009 from the China Health and Nutrition Survey (CHNS). The primary outcome was the risk of CKD, which was defined as the estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. Multivariable logistic regression model was used to examine the relationship of serum Mg concentrations with the risk of CKD.

RESULTS

Included were 8,277 individuals, with an overall CKD prevalence of 11.8% (n = 977). Compared with the first quartile of serum Mg, the multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for participants in the second, third, and fourth quartiles of serum Mg were 0.74 (0.58, 0.93), 0.87 (0.69, 1.11) and 1.29 (1.03, 1.61), respectively. Similar results were observed in our several sensitivity analyses. Restricted cubic spline analysis demonstrated a nonlinear (similar "J"-shaped) association between serum Mg concentrations and the risk of CKD (Pnonlinearity <0.001), with a threshold at around a serum Mg value of 2.2 mg/dL.

CONCLUSIONS

Our results suggested a similar "J"-shaped association between serum Mg concentration and the risk of CKD among Chinese adults. Further large prospective studies are needed to verify these findings.

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.

Association between magnesium intake and the risk of anemia among adults in the United States

Background

Magnesium deficiency is related to an increased risk of anemia, but epidemiological evidence supporting this association remains scarce. The purpose of the present survey was to evaluate the relationship between dietary magnesium intake and the risk of anemia.

Methods

In total, 13,423 participants aged 20-80 years were enrolled using data from the National Health and Nutrition Examination Survey 2011-2016. Magnesium consumption was evaluated using 24 h dietary recalls. Multivariable generalized linear models were developed to demonstrate the association between dietary magnesium intake and the prevalence of anemia.

Results

An inverse association between dietary magnesium intake and the risk of anemia was detected based on a full adjustment model. We evaluated magnesium intake as a categorical variable (five quartiles). Compared with the lowest value, the highest multivariate adjusted odds ratio (95% confidence interval) for anemia was 0.64 (0.46-0.89). Stratified analyses revealed a reverse relationship between magnesium intake and anemia in women. However, no significant association was observed in men (p _{for trend} = 0.376). A similar reverse association was found among the older group (aged ≥60 years).

Conclusion

Magnesium deficiency is closely related to a higher rate of anemia occurrence, especially among women and older Americans. Further larger-scale prospective studies are required to confirm these conclusions.

Magnesium supplementation and iron status among female students: the intervention study

Background

Literature data indicate the benefit of magnesium (Mg) supplementation. The aim of this study was to examine the effect of short-term Mg supplementation on iron status in healthy female participants.

Methods

One hundred healthy female students of the University of Belgrade - Faculty of Pharmacy participated the study during eleven intervention days. Students ingested Mg preparations with the same dose of the active substance. The analysis included the measurement of serum iron, unsaturated iron binding capacity (UIBC), total iron binding capacity (TIBC), total Mg (tMg), ionized Mg (iMg), complete blood count, met-, carboxyand oxy-haemoglobin (metHgb, COHgb, O2Hgb). Transferrin concentrations and percentage of transferrin saturation (SAT) were calculated manually. The association among the analyzed biochemical parameters was examined using polynomial regression. A principal component analysis (PCA) was used for the evaluation of interdependence between the analyzed parameters.

Results

A statistically significant trend for change in O2Hgb (%) by tertiles of iMg concentrations was found (P = 0.029). Serum tMg reached significant positive correlation with the SAT at concentration levels greater than 0.9 mmol/L, after 11 days of intervention (R2=0.116). Ionized Mg in a concentration higher than 0.6 mmol/L is positively correlated with SAT and serum Fe (R2=0.214; 0.199, respectively). PCA revealed variability of 64.7% for two axes after 11 days.

Conclusions

Mg supplementation leads to an improvement in the certain iron status parameters even in individuals with optimal levels of these indices. However, caution should be exercised when supplementing Mg, and laboratory monitoring of the interaction is required.

A Review of the Action of Magnesium on Several Processes Involved in the Modulation of Hematopoiesis

Magnesium (Mg²⁺) is an essential mineral for the functioning and maintenance of the body. Disturbances in Mg²⁺ intracellular homeostasis result in cell-membrane modification, an increase in oxidative stress, alteration in the proliferation mechanism, differentiation, and apoptosis. Mg²⁺ deficiency often results in inflammation, with activation of inflammatory pathways and increased production of proinflammatory cytokines by immune cells. Immune cells and others that make up the blood system are from hematopoietic tissue in the bone marrow. The hematopoietic tissue is a tissue with high indices of renovation, and Mg²⁺ has a pivotal role in the cell replication process, as well as DNA and RNA synthesis. However, the impact of the intra- and extracellular disturbance of Mg²⁺ homeostasis on the hematopoietic tissue is little explored. This review deals specifically with the physiological requirements of Mg²⁺ on hematopoiesis, showing various studies related to the physiological requirements and the effects of deficiency or excess of this mineral on the hematopoiesis regulation, as well as on the specific process of erythropoiesis, granulopoiesis, lymphopoiesis, and thrombopoiesis. The literature selected includes studies in vitro, in animal models, and in humans, giving details about the impact that alterations of Mg²⁺ homeostasis can have on hematopoietic cells and hematopoietic tissue.

The prevalence of serum magnesium and iron deficiency anaemia among Sudanese women in early pregnancy: a cross-sectional study

Background

Anaemia during pregnancy is associated with adverse maternal and child health. Investigations of anaemia and its predictors among pregnant women are needed for preventive measures.

Methods

A cross-sectional study was conducted to investigate the prevalence and determinants of anaemia in early pregnancy in Khartoum, Sudan. Clinical characteristics were gathered using a questionnaire. Serum ferritin, magnesium and high-sensitivity C-reactive protein (hs-CRP) were measured using different laboratory methods.

Results

Of the 180 women in the study, 65.0% had anaemia (haemoglobin [Hb] <11 g/dl), 0.6% had severe anaemia (Hb <7 g/dl), 38.9% had iron deficiency (serum ferritin <15 μg/l), 30.6% had iron deficiency anaemia (<11 g/dl and serum ferritin <15 μg/l) and 57.2% had magnesium deficiency (<1.80 mg/dl). There was no significant difference in the age, parity, gestational age, body mass index (BMI) and hs-CRP between anaemic and non-anaemic pregnant women. Anaemic pregnant women had significantly lower levels of serum ferritin and serum magnesium. While age, parity, gestational age, BMI and hs-CRP were not associated with anaemia, low serum ferritin (odds ratio [OR] 0.97 [95% confidence interval {CI} 0.96 to 0.99]) and low serum magnesium (OR 0.91 [95% CI 0.84 to 0.99]) were associated with anaemia. There were significant positive correlations between Hb and serum ferritin (r=0.382, p<0.001) and serum magnesium (r=0.192, p=0.010).

Conclusion

The role of magnesium as a possible contributing factor to anaemia in pregnancy has important implications for prevention and treatment of these women.

Micromotors for Active Delivery of Minerals toward the Treatment of Iron Deficiency Anemia

As the most common nutritional disorder, iron deficiency represents a major public health problem with broad impacts on physical and mental development. However, treatment is often compromised by low iron bioavailability and undesired side effects. Here, we report on the development of active mineral delivery vehicles using Mg-based micromotors, which can autonomously propel in gastrointestinal fluids, aiding in the dynamic delivery of minerals. Iron and selenium are combined as a model mineral payload in the micromotor platform. We demonstrate the ability of our mineral-loaded micromotors to replenish iron and selenium stores in an anemic mouse model after 30 days of treatment, normalizing hematological parameters such as red blood count, hemoglobin, and hematocrit. Additionally, the micromotor platform exhibits no toxicity after the treatment regimen. This proof-of-concept study indicates that micromotor-based active delivery of mineral supplements represents an attractive approach toward alleviating nutritional deficiencies.

Magnesium Intake and Sleep Disorder Symptoms: Findings from the Jiangsu Nutrition Study of Chinese Adults at Five-Year Follow-Up

(1) Background: In clinical trials, dietary magnesium use can improve insomnia symptoms. However, little is known about the association between dietary magnesium consumption and sleep disorder symptoms including daytime falling asleep, sleepiness and snoring at the population level. (2) Methods: We used data from 1487 adults aged 20 and above attending the Jiangsu Nutrition Study. At baseline in 2002, dietary magnesium was assessed by 3-day weighed food records. At follow-up in 2007, sleep disorder symptoms, including daytime falling asleep, sleepiness and snoring at night, were gathered using a sleep questionnaire. (3) Results: The mean intake of magnesium was 332.5 mg/day. In total, 5.3%, 13.2% and 35.7% of the subjects reported daytime falling asleep, daytime sleepiness, and snoring during sleep, respectively. Compared with the lowest quartile of magnesium intake, the highest quartile was associated with decreased likelihood of falling asleep (odds ratio (OR) 0.12 (0.02, 0.57)) in women but not in men after adjusting for demographic, anthropometric, lifestyle factors, hypertension, and overall dietary patterns. No associations were found between dietary magnesium intake and daytime sleepiness nor night snoring in either gender. (4) Conclusions: Dietary magnesium intake may have long-term benefits in reducing the likelihood of daytime falling asleep in women.

Multivariable Analysis of Nutritional and Socio-Economic Profiles Shows Differences in Incident Anemia for Northern and Southern Jiangsu in China

Anemia is a prevalent public health problem associated with nutritional and socio-economic factors that contribute to iron deficiency. To understand the complex interplay of risk factors, we investigated a prospective population sample from the Jiangsu province in China. At baseline, three-day food intake was measured for 2849 individuals (20 to 87 years of age, mean age 47 ± 14, range 20-87 years, 64% women). At a five-year follow-up, anemia status was re-assessed for 1262 individuals. The dataset was split and age-matched to accommodate cross-sectional (n = 2526), prospective (n = 837), and subgroup designs (n = 1844). We applied a machine learning framework (self-organizing map) to define four subgroups. The first two subgroups were primarily from the less affluent North: the High Fibre subgroup had a higher iron intake (35 vs. 21 mg/day) and lower anemia incidence (10% vs. 25%) compared to the Low Vegetable subgroup. However, the predominantly Southern subgroups were surprising: the Low Fibre subgroup showed a lower anemia incidence (10% vs. 27%), yet also a lower iron intake (20 vs. 28 mg/day) compared to the High Rice subgroup. These results suggest that interventions and iron intake guidelines should be tailored to regional, nutritional, and socio-economic subgroups.

Hb level, iron intake and mortality in Chinese adults: a 10-year follow-up study

Anaemia is prevalent in developing countries and is commonly Fe deficiency related. We aimed to assess the association between Fe status, Fe intake and mortality among Chinese adults. We prospectively studied 8291 adults aged 20-98 years with a mean follow-up of 9·9 years. All participants were measured for Hb at baseline in 2002. Food intake, measured by 3-d weighed food record (n 2832), and fasting serum ferritin were measured. We documented 491 deaths (including 192 CVD and 165 cancer deaths) during 81 527 person-years of follow-up. There was a U-shaped association between Hb levels and all-cause mortality. Compared with the second quartile of Hb (121 g/l), the first (105) and fourth quartile (144) had hazard ratios (HR) of 2·29 (95 % CI 1·51, 3·48) and 2·31 (95 % CI 1·46, 3·64) for all-cause mortality in women. In men, compared with third quartile of Hb (143 g/l), first (122) and fourth quartiles (154) had 61 and 65 % increased risk of all-cause mortality. Anaemia was associated with an increased risk of all-cause and CVD mortality in men but not in women after adjusting for potential confounders. Low and high Fe intake as percentage of Chinese recommended nutrient intake (RNI) were positively associated with all-cause mortality in women but not in men. In women, across quartiles of relative Fe intake, HR for all-cause mortality were 2·55 (95 % CI 0·99, 6·57), 1·00, 3·12 (95 % CI 1·35, 7·18) and 2·78 (95 % CI 1·02, 7·58). Both low and high Hb levels are related to increased risk of all-cause mortality. Both low and high intake of Fe as percentage of RNI was positively associated with mortality in women.

Association between predominantly plant-based diets and iron status in Chinese adults: a cross-sectional analysis

Current evidence of the relationship between diets and Fe status is mostly derived from studies in developed countries with Western diets, which may not be translatable to Chinese with a predominantly plant-based diet. We extracted data that were nationally sampled from the 2009 wave of China Health and Nutrition Survey; dietary information was collected using 24-h recalls combined with a food inventory for 3 consecutive days. Blood samples were collected to quantify Fe status, and log-ferritin, transferrin receptor and Hb were used as Fe status indicators. In total, 2905 (1360 males and 1545 females) adults aged 18–50 years were included for multiple linear regression and stratified analyses. The rates of Fe deficiency and Fe-deficiency anaemia were 1·6 and 0·7 % for males and 28·4 and 10·7 % for females, respectively. As red meat and haem Fe consumption differed about fifteen to twenty times throughout the five groups, divided by quintiles of animal protein intake per 4·2 MJ/d, only Fe status as indicated by log-ferritin (P=0·019) and transferrin receptor (P=0·024) concentrations in males was shown to be higher as intakes of animal foods increased. Log-ferritin was positively associated with intakes of red meat (B=0·3 %, P=0·01) and haem Fe (B=12·3 %, P=0·010) in males and with intake of non-haem Fe in females (B=2·2 %, P=0·024). We conclude that diet has a very limited association with Fe status in Chinese adults consuming a traditional Chinese diet, and a predominantly plant-based diet may not be necessarily responsible for poor Fe status.

Dietary pattern, serum magnesium, ferritin, C-reactive protein and anaemia among older people

BACKGROUND & AIMS

Epidemiological data of dietary patterns and anaemia among older Chinese remains extremely scarce. We examined the association between dietary patterns and anaemia in older Chinese, and to assess whether biomarkers of serum magnesium, C-reactive protein (CRP) and serum ferritin can mediate these associations.

METHODS

We analysed the 2009 China Health and Nutrition Survey data (2401 individuals aged ≥60 years for whom both dietary and biomarker data are available). Dietary data was obtained using 24 h-recall over three consecutive days. Fasting blood samples and anthropometry measurement were also collected. Factor analysis was used to identify dietary patterns. Factor scores representing dietary patterns were used in Poisson regression models to explore the association between each dietary pattern and anaemia.

RESULTS

Of the 2401 participants, 18.9% had anaemia, 1.9% had anaemia related to inflammation (AI), and 1.3% had iron-deficiency anaemia (IDA). A traditional dietary pattern (high intake of rice, pork and vegetables) was positively associated with anaemia; a modern dietary pattern (high intake of fruit and fast food) was inversely associated with anaemia. Progressively lower magnesium and BMI levels were associated with increasing traditional dietary quartiles; while a progressively higher magnesium and BMI levels were associated with increasing modern dietary quartiles (p < 0.001). There were no significant differences (p > 0.05) in CRP and serum ferritin across quartiles for either dietary pattern. In the fully adjusted model, the prevalence ratio (PR) of anaemia, comparing the fourth quartile to the first quartile, was 1.75 (95% CI: 1.33; 2.29) for a traditional dietary pattern, and 0.89 (95% CI: 0.68; 1.16) for a modern dietary pattern. The association between dietary patterns and anaemia is mediated by serum magnesium.

CONCLUSION

Traditional dietary pattern is associated with a higher prevalence of anaemia among older Chinese. Future studies need to examine whether correcting micronutrient deficiency (e.g. magnesium) by promoting overall healthy diet, rather than iron supplementation, is a suitable strategy for anaemia prevention in older Chinese people.

Pilot Study of the Association of Anemia with the Levels of Zinc, Copper, Iron, Calcium, and Magnesium of Children Aged 6 Months to 3 Years in Beijing, China

This study sought to explore the relationship between anemia in children and levels of five minerals in blood. A sample consisted of 242 normal and 304 anemic children paired by sex and age. Hematological parameters were assessed using the Sysmex xs-800i hematology analyzer. Levels of zinc (Zn), copper (Cu), iron (Fe), magnesium (Mg), and calcium (Ca) were measured by polarographic analysis. Differences in these elements between the anemic and normal groups were compared by ANOVA. Relationships between Ca, Zn, Fe, Cu, Mg, and Hb levels were tested by Pearson's correlation analysis. The Mg level (1.51 ± 0.30 mmol/L) of the moderately anemic group (≤90 g/L) was significantly higher than that (1.36 ± 0.30 mmol/L) of the mildly anemic (90 g/L ≤Hb <110 g/L) and normal groups (1.31 ± 0.30 mmol/L) (p < 0.05). The rate of moderate anemia (13.7 %) in the higher Mg group (Mg >1.57 mmol/L) was higher than that (5.3 %) of the lower Mg group (Mg ≤1.57 mmol/L) (p < 0.01). The rate of moderate anemia (12.8 %) in the lower Fe group (≤78.4 umol/L) was higher than that (6.2 %) of the higher Fe group (>78.4 umol/L) (p < 0.05). Hemoglobin was inversely correlated with Mg levels in the anemic group (p < 0.05). These results indicate that blood levels of Mg and Fe were correlated with anemic children aged 6 months to 3 years. To prevent and treat anemia better, a combination of the levels of Hb, Mg, and Fe in whole blood is required.

Disparity of anemia prevalence and associated factors among rural to urban migrant and the local children under two years old: a population based cross-sectional study in Pinghu, China

BACKGROUND

Number of internal rural to urban migrant children in China increased rapidly. The disparity of anemia prevalence among them and children of local permanent residents has been reported, both in big and middle-size cities. There has been no population-based study to explore the associated factors on feeding behaviors in small size cities of China. This study aimed to identify whether there was a difference in the prevalence of anemia between children of rural to urban migrant families and local children under 2 years old in a small coastal city in China, and to identify the associated factors of any observed difference.

METHODS

A community-based, cross-sectional survey was conducted in Pinghu, a newly-developing city in Zhejiang Province, China, among the caregivers of 988 children (667 who were identified as children of migrants and 321 locals) aged 6-23 months. Disparity of anemia prevalence were reported. Association between anemia prevalence and socio-economic status and feeding behaviors were explored among two groups respectively.

RESULTS

Anemia prevalence among the migrant and local children was 36.6% and 18.7% respectively (aPR 1.86, 95% CI 1. 40 to 2.47). Results from adjusted Poisson models revealed: having elder sibling/s were found as an associated factor of anemia with the aPR 1.47 (95% CI 1.16 to 1.87) among migrant children and 2.58 (95% CI 1.37 to 4.58) among local ones; anemia status was associated with continued breastfeeding at 6 months (aPR = 1.57, 95% CI 1.15 to 2.14) and lack of iron-rich and/or iron-fortified foods (aPR = 0.68, 95% CI 0.50 to 0.89) among the migrant children but not among local ones.

CONCLUSION

Anemia was more prevalent among migrant children, especially those aged 6-11 months. Dislike their local counterparts, migrant children were more vulnerable at early life and seemed sensitive to feeding behaviors, such as, over reliance on breastfeeding for nutrition after aged 6 months, lack of iron-rich and/or iron-fortified foods. Future strategies to narrow the gap of anemia prevalence between the migrant and local children should target more susceptible groups and through improvement of feeding practices among younger children in those kinds of newly-developing areas of China.

Association between serum magnesium and anemia: china health and nutrition survey

The role of magnesium in anemia remains unclear. We aimed to investigate the prevalence of anemia and its association with serum magnesium in a nationally representative sample. A total of 8,511 participants aged 18 years and over were recruited in this cross-sectional survey in 2009. Anemia was defined as hemoglobin concentration less than 130 g/l for men and less than 120 g/l for women. Multiple logistic regression models were applied to explore the association of magnesium and anemia. The prevalence of anemia in total was 14.0% with 8.8% for men and 18.5% for women (P<0.0001), respectively. The interaction terms between magnesium and gender and ferritin were significant (P<0.001). In men with serum ferritin≥15 ng/ml, compared with the first quartile of magnesium, the odds ratios (ORs) and 95% confidence intervals (CIs) for those in the second, third, and fourth quartile of magnesium were 0.65 (0.46, 0.91), 0.77 (0.55, 1.09), and 0.63 (0.45, 0.89), respectively, after adjusting multiple confounders. Likewise, in women with serum ferritin≥15 ng/ml, the corresponding ORs (95% CIs) were 0.71 (0.56, 0.91), 0.64 (0.49, 0.84), and 0.53 (0.40, 0.71). The associations between magnesium and anemia were not significant in neither men nor women with serum ferritin<15 ng/ml. Serum magnesium was inversely associated with anemia in both men and women, in particular among adults with high serum ferritin levels.

Exposure to the Chinese famine in early life and the risk of anaemia in adulthood

Background

Famine exposure during the early stage of life is related to a number of adulthood diseases. The objective of this study was to examine the association of early life exposure to the famine in China (1959–1961) with the risk of anaemia in adulthood.

Methods

We used the data of 2007 adults born between 1954 and 1964 in Jiangsu province from the 2002 Chinese National Nutrition and Health Survey. Anaemia was defined as haemoglobin concentration <12 g/dl in women and <13 g/dl in men.

Results

Prevalence of anaemia in adulthood in nonexposed, fetal-exposed, early-childhood, mid-childhood, and late-childhood exposed to famine groups were 26.0%, 33.8%, 28.1%, 28.2% and 29.7%, respectively. Overall, fetal-exposed to famine was associated with 37% increased risk of anaemia as compared with those non-exposed after adjusting for income, education, place of residence, smoking, alcohol drinking, job, hypertension and BMI; relative risk (95% confidence interval) (RR (95% CI)) was 1.37 (1.09, 1.71). In general, this association appeared to be stronger among men, those who were currently overweight or obese, or those of lower educational levels. Corresponding RR (95% CI) was 1.87 (1.21-2.87), 1.75 (1.20-2.56), and 2.07 (1.37-3.12), respectively.

Conclusions

Fetal exposure to the Chinese famine was associated with an increased risk of anaemia in adulthood.

Monosodium glutamate intake increases hemoglobin level over 5 years among Chinese adults

The aim of this analysis was to determine the relationship between monosodium glutamate (MSG) intake and change in hemoglobin (Hb) levels and the risk of anemia over 5 years in 1197 Chinese men and women who participated in the Jiangsu Nutrition Study (JIN). MSG intake and Hb were quantitatively assessed in 2002 and followed up in 2007. Diet and lifestyle factors were assessed at both time points. There was a positive association between MSG intake and increase in Hb among men but not women. In the multivariate model adjusting for demographic and lifestyle factors as well as baseline dietary pattern, the beta values and 95% confidence interval for Hb changes across quartiles of MSG intake were 0, 0.67(0.04-1.29), 0.99(0.38-1.60), 0.73(0.13-1.34) among men (p for trend 0.091); 0, -0.01(-0.45-0.43), 0.23(-0.25-0.71), and -0.45(-0.96-0.05) among women (p for trend 0.087). Among anemic participants at baseline, there was a significant inverse association between MSG intake and the risk of anemia at follow-up. Comparing extreme quartiles of MSG intake among those anemic at baseline, the relative risk for persistent anemia at follow-up was 0.49 (95% CI: 0.28-0.86, p < 0.01). The association was independent of dietary patterns and lifestyle factors. A dose-response relationship between MSG intake and increase in Hb levels among anemic participants was seen. MSG intake may have independent Hb-increasing effects, especially among men and those anemic at baseline.

Micronutrients deficiency and associated sociodemographic factors in Chinese children

BACKGROUND

Although the prevalence of malnutrition has decreased, micronutrient deficiency still exists among children. While iron level has been studied, limited information on serum levels of zinc in Chinese children is available. This study aims to describe the status of micronutrients and its association with sociodemographic factors, and to assess associated risk factors.

METHODS

A cross-sectional study was performed on 1375 Chinese preschool children. Venous blood samples were collected and analyzed for zinc and iron by atomic absorption spectrophotometry. Sociodemographic information was obtained from self-administered questionnaires given to the parents.

RESULTS

The high prevalence of low serum zinc (38.2%) and iron (24.3%) was found. Children from rural preschools had the lowest zinc levels, whereas those from urban preschools had the lowest iron levels. Children living in small houses had the highest prevalence of low serum zinc (47.1%), and children from small families (≤3 persons) had a higher prevalence of low serum zinc than those from large families (41.8% vs. 34.1%).

CONCLUSIONS

Our findings in the recent socioeconomic development of China suggest the need for continuous monitoring of nutritional factors and highlight the importance of public health implication in preschool children even in developed regions.