The status of vitamin B12 and folate among Chinese women: a population-based cross-sectional study in northwest China

Nonlinear Relationship Between Maternal and Cord Blood Vitamin B12 and Folate from a Chinese Population-Based Study

Purpose

There remains a data gap on vitamin B12 and folate level in maternal and child populations. This study aimed to assess the status of vitamin B12 and folate in maternal serum (MS) and umbilical cord serum (UCS).

Materials and Methods

This was a planned secondary analysis of a case-control study. A total of 858 pregnant women during late pregnancy and their newborns in the hospitals of China were included. Maternal peripheral venous blood and neonatal umbilical cord blood were collected to determine serum vitamin B12 and folate concentration. Relationship of vitamin B12 or folate concentration between MS and UCS was assessed by a quantile regression model and the non-linear relationship between them was examined.

Results

Nutritional status of serum folate was better than that of vitamin B12. Prevalence of deficiency in MS vitamin B12 and folate was 73.4% and 14.2%, respectively and these figures were about 17.8% and 0.1% in UCS. Both vitamin B12 and folate levels in UCS were significantly higher than those in MS (vitamin B12: 321.0 pg/mL vs 158.3 pg/mL, folate: 16.5 ng/mL vs 7.0 ng/mL, P <0.001). The median UCS-MS ratio of vitamin B12 and folate was 2.0 (95% CI: 1.94-2.06) and 2.4 (95% CI: 2.30-2.53), respectively. The levels of folate and vitamin B12 in UCS increased nonlinearly with their increase in MS which presented an inverted U-shaped curve.

Conclusion

Deficiency in vitamin B12 and folate in the women during late pregnancy in China is prevalent. Nutritional status of the two vitamins in umbilical cord serum is correlated nonlinearly with that in maternal serum. Folic acid supplementation may be accompanied with vitamin B12 to improve status of vitamin B12 and folate during pregnancy.

Folate and Its Significance in Depressive Disorders and Suicidality: A Comprehensive Narrative Review

Depressive disorders pose significant challenges to global public health, necessitating effective prevention and management strategies. Notably, the occurrence of suicide frequently coincides with depressive episodes. Suicide is as a paramount global health concern that demands efficacious preventive strategies. Current psychiatric approaches heavily rely on pharmacological interventions but have had limited success in addressing the global burden of mental health issues. Suboptimal nutrition, with its impact on the neuroendocrine system, has been implicated in the underlying pathology of depressive disorders. Folate, a group of water-soluble compounds, plays a crucial role in various central nervous system functions. Depressed individuals often exhibit low levels of serum and red blood cell folate. Multiple studies and systematic reviews have investigated the efficacy of folic acid and its derivative, L-methylfolate, which can cross the blood-brain barrier, as stand-alone or adjunct therapies for depression. Although findings have been mixed, the available evidence generally supports the use of these compounds in depressed individuals. Recent studies have established links between the one-carbon cycle, folate-homocysteine balance, immune system function, glutamate excitation via NMDA (N-methyl-D-aspartate) receptors, and gut microbiome eubiosis in mood regulation. These findings provide insights into the complex neurobiological mechanisms underlying the effects of folate and related compounds in depression. Through a comprehensive review of the existing literature, this study aims to advance our understanding of the therapeutic potential of folic acid and related compounds in depression treatment. It also seeks to explore their role in addressing suicidal tendencies and shed light on the neurobiological mechanisms involved, leveraging the latest discoveries in depression research.

Determinants of vitamin B12 deficiency in patients with type-2 diabetes mellitus - A primary-care retrospective cohort study

BACKGROUND

Like many developed nations, the prevalence of both older people and type-2 diabetes mellitus (T2DM) in Singapore is rising. This demographic shift predisposes the population to greater risks of both frailty and its complications that can be further aggravated by vitamin B12 deficiency -a highly prevalent associated variable that is potentially modifiable. Indeed, B12 deficiency adversely impacts the neuro-cognitive, haematological, and even the immune systems; jeopardizing our aspirations for successful aging. Despite this, many patients with T2DM in primary care remain unscreened due to a lack of clear guidelines for regular B12 screening. We therefore investigated the determinants of B12 deficiency in community-dwelling patients with T2DM, with the aim of profiling patients most in need of B12-deficiency screening.

METHODS

B12 deficiency was evaluated using a retrospective cross-sectional cohort of 592 primary-care patients with T2DM, recruited from 2008 to 2011 from a Polyclinic in Singapore.

RESULTS

B12 deficiency (serum B12 < 150 pmol/L) was present in 164 (27.7%) patients and was associated with a higher "metformin daily dose" (OR = 2.79; 95% CI, 2.22-3.48, P < 0.001); "age ≥ 80 years" (OR = 2.86; 95% CI, 1.31-6.25, P = 0.008); "vegetarianism" (OR = 21.61; 95% CI, 4.47-104.44, P < 0.001); and "folate deficiency" (OR = 2.04; 95% CI, 1.27-3.28, P = 0.003). Conversely, "Prescribed B12 supplementation" was associated with a lower odds of B12 deficiency (OR = 0.37; 95% CI: 0.22-0.61, P < 0.001). The area under the receiver operating characteristic curve was 0.803 (95% CI: 0.765-0.842). "Metformin daily dose" correlated interchangeably with "Metformin 1-year cumulative dose" (r = 0.960; P < 0.01), and also associated linearly with "duration of diabetes" (B = 0.113, P < 0.0001). Independent of the duration of T2DM, 29.3% of the B12-deficient patients needed > 1 screening test before the detection of B12 deficiency.

CONCLUSIONS

Primary-care screening for B12 deficiency should be part of the annual laboratory review of patients with T2DM regardless of the duration of T2DM -especially when they are prescribed ≥ 1.5 g/day of metformin; ≥ 80 years old; vegetarian; and not prescribed B12 supplementation. Concurrent evaluation for associated folate (vitamin B9) deficiency is essential when addressing T2DM-associated B12 deficiencies. Current "Metformin daily dose" is an accurate proxy of both cumulative metformin exposure and duration of T2DM.

Ultra-Processed Food Consumption Is Related to Higher Trans Fatty Acids, Sugar Intake, and Micronutrient-Impaired Status in Schoolchildren of Bahia, Brazil

Ultra-processed food (UPF) consumption impacts nutrient intake and plays an important role in non-communicable diseases (NCD), even among schoolchildren. This cross-sectional study aimed to characterize the food consumption of this population and its relationship with laboratory and anthropometric aspects. A sample of 190 subjects aged 5 to 19 y was randomly selected for dietary, laboratory, and anthropometric assessment. Statistical inference was calculated using Spearman's correlation. Excess weight was observed in 34%, a high Waist-to-Height Ratio in 9%, and hypertriglyceridemia in 17% of the subjects, higher among those from urban schools (45%, p = 0.011; 15%, p = 0.015; 24%, p = 0.026, respectively). UPF consumption represented 21% of caloric intake and showed a positive correlation with trans fatty acids (r = 0.70) and sugar (r = 0.59) intake. Unprocessed food consumption showed a weak, but significant, correlation with Body Mass Index (r = 0.22) and Waist Circumference (r = 0.23), while processed meat showed a negative correlation with serum ferritin (r = -0.16) and vitamins D (r = -0.20) and B₁₂ (r = -0.15). These findings highlight the need for public policies to promote Food and Nutritional Security for schoolchildren to prevent NCD and nutritional deficiencies.

Association of maternal folate use and reduced folate carrier gene polymorphisms with the risk of congenital heart disease in offspring

Although it is generally recognized that genetic and environmental factors are associated with the risk of congenital heart disease (CHD), the mechanism remains largely uncertain. This study aimed to investigate the association of maternal folate use, the time when folate use was started, and polymorphisms of the reduced folate carrier (RFC1) gene with the risk of CHD in offspring of Chinese descent, which can help provide new insight into the etiology of folate-related birth defects. A case-control study of 683 mothers of CHD patients and 740 mothers of healthy children was performed. The present study showed that mothers who did not use folate were at a significantly increased risk of CHD (OR=2.04; 95% CI: 1.42-2.93). When compared with those who started using folate prior to conception, mothers who started using folate from the first trimester of pregnancy (OR=1.90; 95% CI: 1.43-2.54) or from the second trimester of pregnancy (OR=8.92; 95% CI: 4.20-18.97) had a significantly higher risk of CHD. Maternal RFC1 gene polymorphisms at rs2236484 (AG vs AA: OR=1.79 [95% CI: 1.33-2.39]; GG vs AA: OR=1.64 [95% CI: 1.15-2.35]) and rs2330183 (CT vs CC: OR=1.54 [95% CI: 1.14-2.09]) were also significantly associated with CHD risk. Additionally, the risk of CHD was significantly decreased among mothers who had variant genotypes but used folate when compared with those who had variant genotypes and did not use folate.Conclusion: In those of Chinese descent, maternal folate use and the time when use started are significantly associated with the risk of CHD in offspring. Furthermore, maternal folate supplementation may help to offset some of the risks of CHD in offspring due to maternal RFC1 genetic variants. What is Known: • Folate use could help prevent CHD, but the relationship between the time when folate use is started and CHD has not received sufficient attention. • Studies have assessed the associations of folate metabolism-related genes with CHD, but genes involved in cellular transportation of folate, such as the RFC1 gene, have not garnered enough attention. What is New: • In those of Chinese descents, the time when folate use is started is significantly associated with the risk of CHD in offspring. • Maternal RFC1 polymorphisms were significantly associated with the risk of CHD. • Folate supplementation may help to offset some risks of CHD due to RFC1 genetic variants.

Folic acid supplementation acts as a chemopreventive factor in tumorigenesis of hepatocellular carcinoma by inducing H3K9Me2-dependent transcriptional repression of LCN2

The effects and mechanisms of folic acid (FA) as a chemopreventive agent for tumorigenesis of hepatocellular carcinoma (HCC) remain unclear. In this study, the QSG-7701, a human normal liver cell line, was cultured in different FA levels (High, Normal or No) for 6 months. Then, the biological characteristics, the expression of main stem cell-like genes or epithelial-mesenchymal transition (EMT) related genes and the tumorigenicity in vivo of cells cultured in different treatment groups were detected. Our results showed that No FA improved the malignant transformation of cells but High FA depressed the malignant transformation. Meanwhile, cells in different treatment groups were mapped by transcriptome sequencing. Then the relativity of increased LCN2 and decreased FA level was identified and confirmed in vitro and vivo. We also revealed that intracellular control of LCN2 would recover the effects of FA on cell proliferation, cell cycle and tumor formation in vitro and vivo. Finally, our studies displayed that increased FA level induced the down-regulation of LCN2 not by DNA hypermethylation of LCN2 promoter but by promoting the level of histone H3 lysine 9 di-methylation (H3K9Me2) in LCN2 promoter. In conclusion, our studies disclosed the chemopreventive effect of FA supplementation on hepatocarcinogenesis, which partial attributed to the inhibition of LCN2 by regulating histone methylation in promoter. Our results provide a potential mechanism of the chemoprevention of FA supplementation on tumorigenesis of HCC and may be helpful in developing treatment target against HCC.

Maternal folate levels during pregnancy and offspring brain development in late childhood

BACKGROUND

Cumulative evidence shows that low maternal folate levels during pregnancy are associated with offspring neuropsychiatric disorders even in the absence of neural tube defects. However, the relationship between prenatal exposure to folate and brain development in late childhood has been rarely investigated.

METHODS

In 2095 children from a prospective population-based cohort in Rotterdam, the Netherlands, we examined the association of maternal folate levels during pregnancy with downstream brain development in offspring. Maternal folate concentrations were measured from venous blood in early gestation. Child structural neuroimaging data were measured at age 9-11 years. In addition, measures of child head circumference using fetal ultrasound in the third trimester and total brain volume using magnetic resonance imaging at age 6-8 years were used for analyses with repeated assessments of brain development.

RESULTS

Maternal folate deficiency (i.e., <7 nmol/L) during pregnancy was associated with smaller total brain volume (B = -18.7 cm³, 95% CI -37.2 to -0.2) and smaller cerebral white matter (B = -7.2 cm³, 95% CI -11.8 to -2.6) in children aged 9-11 years. No differences in cortical thickness or surface area were observed. Analysis of the repeated brain assessments showed that children exposed to deficient folate concentrations in utero had persistently smaller brains compared to controls from the third trimester to childhood (β = -0.4, 95% CI -0.6 to -0.1).

CONCLUSIONS

Low maternal folate levels during pregnancy are associated with altered offspring brain development in childhood, suggesting the importance of essential folate concentrations in early pregnancy.

Association of antenatal vitamin B complex supplementation with neonatal vitamin B12 status: evidence from a cluster randomized controlled trial

PURPOSE

Evidence about the effect of maternal vitamin B₁₂ supplementation on offspring's vitamin B₁₂ status is limited. The present interventional study sought to evaluate the association of antenatal vitamin B complex supplementation with neonatal vitamin B₁₂ status.

METHODS

In an ongoing cluster randomized controlled trial conducted in three rural counties in northwest China, pregnant women < 20 weeks of gestation were randomized to three treatment groups: blank control, iron supplements, or vitamin B complex supplements. All women were administered folic acid supplements during the periconceptional period. In a sub-study, we collected cord blood samples of 331 participants from the control or vitamin B complex groups in the Xunyi county from January 2017 to December 2017. Plasma concentrations of folate, vitamin B₁₂, and homocysteine were measured. Linear mixed models with a random intercept for cluster were used to compare biochemical indexes between groups after controlling for covariates.

RESULTS

Compared with newborns whose mothers were in the control group, newborns of the vitamin B complex-supplemented women had significantly higher cord plasma vitamin B₁₂ (P = 0.001) and lower homocysteine concentrations (P = 0.043). The association of antenatal vitamin B complex supplementation with cord blood vitamin B₁₂ concentrations appeared to be more pronounced among newborns with high folate status than those with low folate status (P_interaction = 0.060).

CONCLUSIONS

Maternal vitamin B complex supplementation during pregnancy was associated with better neonatal vitamin B₁₂ status in rural northwest China.

Circulating folate concentrations and risk of coronary artery disease: a prospective cohort study in Chinese adults and a Mendelian randomization analysis

BACKGROUND

The association between circulating folate concentrations and risk of coronary artery disease (CAD) has been evaluated in Western populations with inconsistent results; however, the observational and causal associations in Chinese populations with relatively low folate concentrations remain unclear.

OBJECTIVES

We aimed to examine the association of circulating folate concentrations with incident CAD in Chinese adults, and further evaluated the causal relation using Mendelian randomization (MR) analysis.

METHODS

We measured baseline serum folate in 1605 incident CAD cases and 1605 age- and sex-matched controls nested within the Dongfeng-Tongji (DFTJ) cohort, which recruited 27,009 individuals with a mean age of 63.6 y in 2008-2010 and followed up until the end of 2013 (mean: 4.4 y). We quantified the observational association between folate and incident CAD using conditional logistic regression models. A 2-sample MR analysis was performed using summary statistics obtained for genetic variants identified from a genome-wide association study (GWAS) of circulating folate concentrations in participants of European ancestry (n = 37,341) and from the CardiogramplusC4D 1000 genomes-based GWAS meta-analysis (n = 184,305). We also conducted 1-sample MR among 1545 incident CAD cases and 1444 controls with genotyping data in the DFTJ cohort.

RESULTS

In the DFTJ cohort, higher serum folate concentrations were associated with a lower risk of CAD: the OR (95% CI) across sex-specific quartiles of folate (from lowest to highest concentrations) was 1.00 (reference), 0.78 (0.63, 0.97), 0.77 (0.61, 0.97), and 0.75 (0.60, 0.95), respectively (P-trend = 0.01). In the MR analysis, the OR of CAD per SD increase in genetically predicted serum folate was 0.99 (0.82, 1.20) and 0.88 (0.59, 1.32) for European and Chinese populations, respectively.

CONCLUSIONS

We found an inverse association between circulating folate concentrations and incident CAD among Chinese populations. However, we confirmed that there was no genetic evidence to support the causal relation in both European and Chinese populations.

Global folate status in women of reproductive age: a systematic review with emphasis on methodological issues

Inadequate folate status in women of reproductive age (WRA) can lead to adverse health consequences of public health significance, such as megaloblastic anemia (folate deficiency) and an increased risk of neural tube defect (NTD)-affected pregnancies (folate insufficiency). Our review aims to evaluate current data on folate status of WRA. We queried eight databases and the World Health Organization Micronutrients Database, identifying 45 relevant surveys conducted between 2000 and 2014 in 39 countries. Several types of folate assays were used in the analysis of blood folate, and many surveys used folate cutoffs not matched to the assay. To allow better comparisons across surveys, we attempted to account for these differences. The prevalence of folate deficiency was >20% in many countries with lower income economies but was typically <5% in countries with higher income economies. Only 11 surveys reported the prevalence of folate insufficiency, which was >40% in most countries. Overall, folate status data for WRA globally are limited and must be carefully interpreted due to methodological issues. Future surveys would benefit from using the microbiologic assay to assess folate status, along with assay-matched cutoffs to improve monitoring and evaluation of folic acid interventions, thus informing global efforts to prevent NTDs.

Should vitamin B12 status be considered in assessing risk of neural tube defects?

There is a strong biological premise for including vitamin B₁₂ with folic acid in strategies to prevent neural tube defects (NTDs), due to the closely interlinked metabolism of these two vitamins. For example, reduction of B₁₂ deficiency among women of reproductive age could enhance the capacity of folic acid to prevent NTDs by optimizing the cellular uptake and utilization of natural folate cofactors. Vitamin B₁₂ might also have an independent role in NTD prevention, such that adding it in fortification programs might be more effective than fortifying with folic acid alone. Globally, there is ample evidence of widespread vitamin B₁₂ deficiency in low‐ and middle‐income countries, but there is also considerable divergence of vitamin B₁₂ status across regions, likely due to genetic as well as nutritional factors. Here, I consider the evidence that low vitamin B₁₂ status may be an independent factor associated with risk of NTDs, and whether a fortification strategy to improve B₁₂ status would help reduce the prevalence of NTDs. I seek to identify knowledge gaps in this respect and specify research goals that would address these gaps.

Prevalence and possible factors associated with anaemia, and vitamin B 12 and folate deficiencies in women of reproductive age in Pakistan: analysis of national-level secondary survey data

OBJECTIVE

To determine the prevalence and possible factors associated with anaemia, and vitamin B₁₂ and folate deficiencies in women of reproductive age (WRA) in Pakistan.

METHODS

A secondary analysis was conducted on data collected through the large-scale National Nutrition Survey in Pakistan in 2011. Anaemia was defined as haemoglobin levels <12 g/dL, vitamin B₁₂ deficiency as serum vitamin B₁₂ levels of <203 pg/mL (150 pmol/L) and folate deficiency as serum folate levels <4 ng/mL (10 nmol/L).

RESULTS

A total of 11 751 blood samples were collected and analysed. The prevalence of anaemia, vitamin B₁₂ deficiency and folate deficiency was 50.4%, 52.4% and 50.8%, respectively. After adjustment, the following factors were positively associated with anaemia: living in Sindh province (RR 1.07; 95% CI 1.04 to 1.09) P<0.00, food insecure with moderate hunger (RR 1.03; 95% CI 1.00 to 1.06) P=0.02, four or more pregnancies (RR 1.03; 95% CI 1.01 to 1.05) P<0.00, being underweight (RR 1.03; 95% CI 1.00 to 1.05) P=0.02, being overweight or obese (RR 0.95; 95% CI 0.93 to 0.97) P<0.00 and weekly intake of leafy green vegetables (RR 0.98; 95% CI 0.95 to 1.00) P=0.04. For vitamin B₁₂ deficiency, a positive association was observed with rural population (RR 0.81; 95% CI 0.66 to 1.00) P=0.04, living in Khyber Pakhtunkhwa province (RR 1.25; 95% CI 1.11 to 1.43) P<0.00 and living in Azad Jammu and Kashmir (RR 1.50; 95% CI 1.08 to 2.08) P=0.01. Folate deficiency was negatively associated with daily and weekly intake of eggs (RR 0.89; 95% CI 0.81 to 0.98) P=0.02 and (RR 0.88; 95% CI 0.78 to 0.99) P=0.03.

CONCLUSIONS

In Pakistan, anaemia, and vitamin B₁₂ and folate deficiencies are a severe public health concern among WRA. Our findings suggest that further research is needed on culturally appropriate short-term and long-term interventions within communities and health facilities to decrease anaemia, and vitamin B₁₂ and folate deficiencies among Pakistani women.

Effect of B Vitamins from Diet on Hypertension

BACKGROUND

In western populations, a higher level of dietary B vitamins intake has been associated with a lower risk of hypertension. However, data in Chinese is limited, whose B vitamins consumption is low and rates of hypertension are high.

AIM OF THE STUDY

To investigate whether the three B vitamins are associated with hypertension in rural Chinese.

METHODS

Cross-sectional survey among 2241 rural Chinese aged 18-80 years was conducted in northwestern China in 2010. Blood pressure was measured by trained medical staff and dietary nutrients were assessed with a semiquantitative food frequency questionnaire.

RESULTS

592 cases of hypertension were newly diagnosed. The deficiency proportions were 20.5% for vitamin B-6, 43.9% for folate and 98.5% for B-12. For females, participants in the highest quartile of B-6 intake had a significantly lower risk of hypertension (OR = 0.69; 95% CI: 0.50-0.93; p for trend <0.05). For males, the multivariable OR for the same comparison was 0.75 (95% CI: 0.56-0.99, p for trend >0.05). No significant associations were observed between B-12, folate intake and hypertension. For females, the highest quartile of both folate and B-6 intake was associated with a reduced risk of hypertension (OR = 0.53; 95% CI: 0.29-0.89), compared with in the middle quartile of both vitamins.

CONCLUSIONS

Higher intake of vitamin B-6 is independently associated with lower risk of hypertension in Chinese rural adults. Among females with high folate intake, the association between B-6 and hypertension was strongest. Additional studies are warrant to establish the causal inference.

Nutrition, One-Carbon Metabolism and Neural Tube Defects: A Review

Neural tube defects (NTDs) are a group of severe congenital malformations, induced by the combined effects of genes and the environment. The most valuable finding so far has been the protective effect of folic acid supplementation against NTDs. However, many women do not take folic acid supplements until they are pregnant, which is too late to prevent NTDs effectively. Long-term intake of folic acid–fortified food is a good choice to solve this problem, and mandatory folic acid fortification should be further promoted, especially in Europe, Asia and Africa. Vitamin B2, vitamin B-6, vitamin B-12, choline, betaine and n-3 polyunsaturated fatty acids (PUFAs) can also reduce the NTD risk by interacting with the one-carbon metabolism pathway. This suggest that multivitamin B combined with choline, betaine and n-3 PUFAs supplementation may have a better protective effect against NTDs than folic acid alone. Genetic polymorphisms involved in one-carbon metabolism are associated with NTD risk, and gene screening for women of childbearing age prior to pregnancy may help prevent NTDs induced by the risk allele. In addition, the consumption of alcohol, tea and coffee, and low intakes of fruit and vegetable are also associated with the increased risk of NTDs, and should be avoided by women of childbearing age.

Dietary intakes and dietary patterns among pregnant women in Northwest China

OBJECTIVE

To describe nutrient intakes, characterize dietary patterns and analyse their associations with sociodemographic characteristics among pregnant women in Shaanxi, China.

DESIGN

Population-based cross-sectional survey.

SETTING

Twenty counties and ten districts in Shaanxi Province of Northwest China, 2013.

SUBJECTS

Women (n 7462) were recruited using a stratified multistage random sampling method to report diets during pregnancy, at 0-12 months (median 3 months; 10th-90th percentile, 0-7 months) after delivery.

RESULTS

Pregnant women had higher intakes of fat, niacin and vitamin E than the nutrient reference values, while most micronutrients such as vitamin A, folate, Ca and Zn were reportedly low. Women in the highest education, occupation and household income groups had higher nutrient intakes than those in the lowest groups. Nutrient intake differences also existed by geographic area, residence and maternal age at delivery. Three dietary patterns were identified: balanced pattern, vegetarian pattern and snacks pattern. Participants with high balanced pattern scores tended to be better educated, wealthier, 25-29 years old at delivery, working outside and living in urban areas and central Shaanxi. Women with high scores on the vegetarian pattern and snacks pattern tended to be in low balanced pattern score groups, and had lower nutrient intakes than those in the high balanced pattern score groups.

CONCLUSIONS

The study suggested that pregnant women in Shaanxi, China had low intakes of most nutrients such as vitamin A, folate and Ca. Dietary patterns and most nutrient intakes varied by sociodemographic characteristics. Targeted programmes are needed to improve dietary intakes and dietary patterns among sociodemographically disadvantaged groups.

Vitamin B12 concentrations in pregnant Colombian women: analysis of nationwide data 2010

Background

Vitamin B12 deficiency is associated with many adverse health outcomes and is highly prevalent worldwide. The present study assesses the prevalence and socio-demographic factors associated with vitamin B12 deficiency in a representative sample of pregnant women in Colombia.

Method

We used data from the cross-sectional, nationally representative survey (ENSIN, 2010). A total of 1.781, (13–49 years old) pregnant women were enrolled. Serum Vitamin B12 a concentration was determined by chemiluminescence and sociodemographic date was assessed by computer-assisted personal interview technology. Multivariate analyses using unordered multinomial logistic regression models were conducted in the main analysis.

Results

Vitamin B12 concentrations ranged from 45 to 1000 pg/mL (mean 299.2 pg/mL, 95 % CI 290.6 to 303.7 pg/mL). A total of 18.6 % of pregnant women had vitamin B12 concentrations below 200 pg/mL and 41.3 % had concentrations between 200 and 300 pg/mL. Being of indigenous ethnicity, living in the east and living in a rural area showed the lowest mean values (273.2 pg/mL, 270.8 pg/mL and 290.1 pg/mL, respectively). The multivariate logistic regression shows that pregnant women belonging to the indigenous ethnic group OR 2.2, (95 % CI 1.1 to 4.3), living in the pacific region (west) OR 4.4, (95 % CI 2.8 to 6.9), or national territories (south) OR 2.3, (95 % CI 1.4 to 3.7) were associated with a higher probability of serum vitamin B12 deficiency.

Conclusion

The prevalence of vitamin B12 deficiency in Colombian pregnant women is substantial. Factors associated with depletion among pregnant women should be considered for future interventions in countries experiencing nutritional transition.