How common is vitamin B-12 deficiency?

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.

The Singer's and the Clinician's Perspective on Vitamin B12 Treatment for Vocal Benefits

INTRODUCTION

There is a belief among vocalists that there are voice benefits from vitamin B₁₂ treatment. Yet there are no previous reports regarding vitamin B₁₂ effects on voice.

OBJECTIVES

To assess the prevalence of vitamin B₁₂ use among singers and their beliefs regarding vitamin B₁₂ therapy.

METHODS

Anonymous online survey administered to singers, singing-teachers, speech-language pathologists, and laryngologists.

RESULTS

A total of 192 participants completed the surveys; 128 singers (68 singing-teachers, 30 speech-language pathologists) and 64 laryngologists. Among singers, 12% have perceived voice benefits from vitamin B₁₂ treatment taken for any reason. Four percent used vitamin B₁₂ for voice benefits; all perceived voice benefits as a result. The leading voice benefits were improved stamina, reduced effort, confidence, and control. Nineteen percent of the singers would recommend vitamin B₁₂ treatment to a friend; 15% of the singing-teachers would recommend it to a student. Among laryngologists, 33% been asked by a singer to prescribe vitamin B₁₂ for voice benefits; 9% have prescribed it in the past. Yet only 3% would you recommend it to a patient. When asked "Do you believe vitamin B₁₂ therapy improves vocal performance?" 31% of the singers responded "Yes," compared with none in the laryngologists. When asked "Do you think the singing community believes vitamin B₁₂ therapy improves vocal performance?" 26% of the singers responded "Yes," compared with 53% of the laryngologists (P = 0.0002).

CONCLUSIONS

There is a discrepancy between the singers' and the laryngologists' beliefs regarding vocal benefits perceived by vitamin B₁₂. Blinded randomized trials are required to verify or refute this belief.

Infant Serum and Maternal Milk Vitamin B-12 Are Positively Correlated in Kenyan Infant-Mother Dyads at 1-6 Months Postpartum, Irrespective of Infant Feeding Practice

Background

Vitamin B-12 is an essential nutrient required for many functions including DNA synthesis, erythropoiesis, and brain development. If maternal milk vitamin B-12 concentrations are low, infants may face elevated risks of deficiency when exclusively breastfed.

Objective

We evaluated cross-sectional associations between infant serum vitamin B-12 concentrations and maternal milk vitamin B-12 concentrations at 1-6 mo postpartum among an unsupplemented population in rural western Kenya, and assessed biological demographic, and dietary characteristics associated with adequate infant serum vitamin B-12.

Methods

We modeled 1) infant serum vitamin B-12 using maternal milk vitamin B-12 concentration with linear regression; and 2) adequate (>220 pmol/L) infant serum vitamin B-12 using hypothesized biological, demographic, and dietary predictors with logistic regression. In both models, we used generalized estimating equations to account for correlated observations at the cluster-level.

Results

The median (quartile 1, quartile 3) infant serum vitamin B-12 concentration was 276 pmol/L (193, 399 pmol/L) and approximately one-third of infants had serum vitamin B-12 ≤220 pmol/L, indicating that they were vitamin B-12 depleted or deficient. There was a positive correlation between maternal milk and infant serum vitamin B-12 (r = 0.36, P < 0.001) and in multivariable analyses, maternal milk vitamin B-12 concentration was significantly associated with infant serum vitamin B-12 adequacy (P-trend = 0.03).

Conclusions

Despite a high prevalence (90%) of maternal milk vitamin B-12 concentrations below the level used to establish the Adequate Intake (<310 pmol/L), there was a low prevalence of infant vitamin B-12 deficiency. We found few factors that were associated with infant vitamin B-12 adequacy in this population, including infant feeding practices, although maternal vitamin B-12 status was not measured. The contribution of maternal milk to infant vitamin B-12 status remains important to quantify across populations, given that maternal milk vitamin B-12 concentration is modifiable with supplementation. This trial was registered at clinicaltrials.gov as NCT01704105.

Micronutrient status in middle childhood and age at menarche: results from the Bogotá School Children Cohort

Childhood intake of animal foods is associated with age at first menstrual period (menarche). It is unknown whether the micronutrients present in these foods could explain this association. Our objective was to investigate the associations of micronutrient status biomarkers in middle childhood with age at menarche. We quantified circulating Hb, ferritin, mean corpuscular volume, Zn, vitamin B12, erythrocyte folate and retinol in 1464 pre-menarcheal girls aged 5–12 years in Bogotá, Colombia, and followed them for a median 5·7 years for the occurrence and date of menarche. We estimated median age at menarche and hazard ratios (HR) with 95 % CI by levels of each biomarker with use of Kaplan–Meier survival probabilities and Cox regression, respectively. Median age at menarche was 12·4 years. Middle childhood Hb was inversely related to age at menarche whereas plasma ferritin was positively associated with this outcome in a linear manner. HR of menarche for every 1sdof Hb (11 g/l) and ferritin (23·2 µg/l) were 1·11 (95 % CI 1·04, 1·18;P=0·001) and 0·94 (95 % CI 0·88, 0·99;P=0·02), respectively, after adjustment for baseline age, C-reactive protein concentration, maternal age at menarche and parity and socioeconomic status. The association with ferritin was stronger in girls aged 9–10 years at baseline. Additional adjustment for baseline height- and BMI-for-age did not change the results. We conclude that higher Fe status in middle childhood is related to later age at menarche whereas Hb concentrations are inversely associated with age at onset of menses.

Vitamin B12 deficiency after esophagectomy with gastric tube reconstruction for esophageal cancer

The aim of this study is to determine the prevalence and incidence of vitamin B12 deficiency after esophagectomy for cancer. It is unknown if patients after esophagectomy with gastric tube reconstruction are at an increased risk for vitamin B12 deficiency. A cross-sectional cohort (group A) and a prospective cohort (group B) of patients who underwent esophagectomy for cancer in two tertiary referral centers in the Netherlands were included. Serum levels of holo-transcobalamin (Holo-TC) and methyl malonic acid (MMA) were determined. Vitamin B12 deficiency was defined as Holo-TC < 21 pmol/L and/or MMA > 0.45 μmol/L. Vitamin B12 status was assessed in group A at a single time point between one and three years postoperatively and before and every three months after resection in group B. Ninety-nine patients were analyzed in group A. The median time between surgery and analysis of vitamin B12 deficiency was 19.3 months. In 11 of 99 (11%) patients, vitamin B12 deficiency was detected. In group B, 5 of 88 (5.6%) patients had vitamin B12 deficiency preoperatively, and another 9 (10.2%) patients developed vitamin B12 deficiency after the operation at a median time of 6 months postoperatively. The estimated one-year incidence of vitamin B12 deficiency was 18.2%. None of the patients with vitamin B12 deficiency had a megaloblastic anemia. Vitamin B12 deficiency can be anticipated in 18% of patients after esophagectomy with gastric tube reconstruction for cancer. During follow-up, Holo-TC and MMA levels should be measured to detect vitamin B12 deficiency and commence treatment timely.

Position paper on vegetarian diets from the working group of the Italian Society of Human Nutrition

BACKGROUND

Interest in vegetarian diets is growing in Italy and elsewhere, as government agencies and health/nutrition organizations are emphasizing that regular consumption of plant foods may provide health benefits and help prevent certain diseases.

METHODS AND RESULTS

We conducted a Pubmed search, up to September, 2015, for studies on key nutrients (proteins, vitamin B12, iron, zinc, calcium, vitamin D, and n-3 fatty acids) in vegetarian diets. From 295 eligible publications the following emerged: Vegetarians should be encouraged to supplement their diets with a reliable source of vitamin B12 (vitamin-fortified foods or supplements). Since the plant protein digestibility is lower than that of animal proteins it may be appropriate for vegetarians to consume more proteins than recommended for the general population. Vegetarians should also be encouraged to habitually consume good sources of calcium, iron and zinc - particularly vegetables that are low in oxalate and phytate (e.g. Brassicaceae), nuts and seeds, and calcium-rich mineral water. Calcium, iron, and zinc bioavailability can be improved by soaking, germination, and sour-dough leavening that lower the phytate content of pulses and cereals. Vegetarians can ensure good n-3 fatty acid status by habitually consuming good sources of a-linolenic acid (walnuts, flaxseeds, chia seeds, and their oils) and limiting linoleic acid intake (corn and sunflower oils).

CONCLUSIONS

Well-planned vegetarian diets that include a wide variety of plant foods, and a reliable source of vitamin B12, provide adequate nutrient intake. Government agencies and health/nutrition organizations should provide more educational resources to help Italians consume nutritionally adequate vegetarian diets.

Prevalence and Predictors of Subclinical Micronutrient Deficiency in German Older Adults: Results from the Population-Based KORA-Age Study

Subclinical micronutrient deficiency in older adults is associated with chronic age-related diseases and adverse functional outcomes. In Germany, the older population is at risk of insufficient micronutrient intake, but representative studies on micronutrient status in old and very old adults are scarce. This study’s objectives were to estimate the prevalence of subclinical vitamin D, folate, vitamin B₁₂ and iron deficiencies among older adults, aged 65 to 93, from the KORA-Age study in Augsburg, Germany (n = 1079), and to examine associated predictors, using multiple logistic regression. Serum concentrations of 25-hydroxyvitamin D (25OHD), folate, vitamin B₁₂, and iron were analyzed. The prevalence of subclinical vitamin D and vitamin B₁₂ deficiencies were high, with 52.0% and 27.3% of individuals having low 25OHD (<50 nmol/L) and low vitamin B₁₂ concentrations (<221 pmol/L), respectively. Furthermore, 11.0% had low iron (men <11.6 µmol/L, women <9.0 µmol/L) and 8.7% had low folate levels (<13.6 nmol/L). Common predictors associated with subclinical micronutrient deficiency included very old age, physical inactivity, frailty and no/irregular use of supplements. Subclinical micronutrient deficiency is a public health concern among KORA-Age participants, especially for vitamins D and B₁₂. The predictors identified provide further rationale for screening high-risk subgroups and developing targeted public health interventions to tackle prevailing micronutrient inadequacies among older adults.

In situ production of active vitamin B12 in cereal matrices using Propionibacterium freudenreichii

The in situ production of active vitamin B12 was investigated in aqueous cereal‐based matrices with three strains of food‐grade Propionibacterium freudenreichii. Matrices prepared from malted barley flour (33% w/v; BM), barley flour (6%; BF), and wheat aleurone (15%; AM) were fermented. The effect of cobalt and the lower ligand 5,6‐dimethylbenzimidazole (DMBI) or its natural precursors (riboflavin and nicotinamide) on active B12 production was evaluated. Active B12 production was confirmed by UHPLC–UV–MS analysis. A B12 content of 12–37 μg·kg⁻¹ was produced in BM; this content increased 10‐fold with cobalt and reached 940–1,480 μg·kg⁻¹ with both cobalt and DMBI. With riboflavin and nicotinamide, B12 production in cobalt‐supplemented BM increased to 712 μg·kg⁻¹. Approximately, 10 μg·kg⁻¹ was achieved in BF and AM and was increased to 80 μg·kg⁻¹ in BF and 260 μg·kg⁻¹ in AM with cobalt and DMBI. The UHPLC and microbiological assay (MBA) results agreed when both cobalt and DMBI or riboflavin and nicotinamide were supplemented. However, MBA gave ca. 20%–40% higher results in BM and AM supplemented with cobalt, indicating the presence of human inactive analogues, such as pseudovitamin B12. This study demonstrates that cereal products can be naturally fortified with active B12 to a nutritionally relevant level by fermenting with P. freudenreichii.

Recurrent anaemia in a patient with lymphocytic gastritis and vitamin B12 deficiency

Lymphocytic gastritis is an idiopathic disease, characterized by intraepithelial infiltration of large numbers of T lymphocytes and often described in association with coeliac disease and Helicobacter pylori infection. Although usually associated with iron deficiency anaemia, there is no description on the association between lymphocytic gastritis and secondary vitamin B₁₂ deficiency anaemia. We describe a rare case of recurrent anaemia in a patient with lymphocytic gastritis reversed with vitamin B₁₂ replacement.

Community pharmacists' knowledge, practices and beliefs about complementary and alternative medicine in Palestine: a cross-sectional study

BACKGROUND

Complementary and alternative medicine (CAM) utilization is dramatically increasing among patients. As community pharmacies are a major provider of CAM products, community pharmacists need to have the sufficient knowledge and information to advice their patients, answer their inquiries and to be proactive in the healthcare process to ensure optimal therapy outputs and minimize both drug-drug and drug-herb interactions. Therefore, the main objective of this study was to assess the knowledge, beliefs, and practices of community pharmacists in Palestine about CAM.

METHODS

The study was conducted in a cross-sectional design in which a questionnaire was administered on a sample of licensed community pharmacists from Palestine. The questionnaire was of 5 sections: demographic and practice details of the participants, practice, beliefs, and knowledge about CAM. Mann-Whitney-U or Kruskal-Wallis tests were used to comparison of different issues as appropriate. P-values of <0.05 were considered significant.

RESULTS

A total of 284 community pharmacists were surveyed, however, 281 were included in the analysis as they met inclusion criteria. Out of the 281, 149 (53.0%) of the participants were males and the rest were females. About 40% of the participants were between 20 to 29 years old. Pharmacists frequently recommended CAM modalities. Exercises (84.0%) and food supplements (82.6%) were the most commonly recommended modalities. In the last year, vitamin B₁₂ was the most frequently prescribed supplement. The median knowledge score was 5 out of 8 and the median beliefs about CAM score was 4.0 out of 7.0.

CONCLUSIONS

CAM recommendations by pharmacists appear to be commonplace. Although their knowledge scores were fair to average, pharmacists still need more education and training about CAM in order to be more qualified to provide better pharmaceutical care and improve their patient's outcome.

Vitamin B12 deficiency

Vitamin B₁₂ (B12; also known as cobalamin) is a B vitamin that has an important role in cellular metabolism, especially in DNA synthesis, methylation and mitochondrial metabolism. Clinical B12 deficiency with classic haematological and neurological manifestations is relatively uncommon. However, subclinical deficiency affects between 2.5% and 26% of the general population depending on the definition used, although the clinical relevance is unclear. B12 deficiency can affect individuals at all ages, but most particularly elderly individuals. Infants, children, adolescents and women of reproductive age are also at high risk of deficiency in populations where dietary intake of B12-containing animal-derived foods is restricted. Deficiency is caused by either inadequate intake, inadequate bioavailability or malabsorption. Disruption of B12 transport in the blood, or impaired cellular uptake or metabolism causes an intracellular deficiency. Diagnostic biomarkers for B12 status include decreased levels of circulating total B12 and transcobalamin-bound B12, and abnormally increased levels of homocysteine and methylmalonic acid. However, the exact cut-offs to classify clinical and subclinical deficiency remain debated. Management depends on B12 supplementation, either via high-dose oral routes or via parenteral administration. This Primer describes the current knowledge surrounding B12 deficiency, and highlights improvements in diagnostic methods as well as shifting concepts about the prevalence, causes and manifestations of B12 deficiency.

Folate Deficiency Is Prevalent in Women of Childbearing Age in Belize and Is Negatively Affected by Coexisting Vitamin B-12 Deficiency: Belize National Micronutrient Survey 2011

Background: Folate deficiency, vitamin B-12 deficiency, and anemia can have adverse effects on birth outcomes. Also, low vitamin B-12 reduces the formation of metabolically active folate.Objectives: We sought to establish the baseline prevalence of and factors associated with folate deficiency and insufficiency, vitamin B-12 deficiency, and anemia among women of childbearing age (WCBA) in Belize.Methods: In 2011, a national probability-based survey was completed among Belizean nonpregnant WCBA aged 15-49 y. Blood samples for determination of hemoglobin, folate (RBC and serum), and vitamin B-12 (plasma) and sociodemographic and health information were collected from 937 women. RBC and serum folate concentrations were measured by microbiologic assay (MBA). Folate status was defined based on both the WHO-recommended radioproteinbinding assay and the assay adjusted for the MBA.Results: The national prevalence estimates for folate deficiency in WCBA, based on serum and RBC folate concentrations by using the assay-matched cutoffs, were 11.0% (95% CI: 8.6%, 14.0%) and 35.1% (95% CI: 31.3%, 39.2%), respectively. By using the assay-matched compared with the WHO-recommended cutoffs, a substantially higher prevalence of folate deficiency was observed based on serum (6.9% absolute difference) and RBC folate (28.9% absolute difference) concentrations. The prevalence for RBC folate insufficiency was 48.9% (95% CI: 44.8%, 53.1%). Prevalence estimates for vitamin B-12 deficiency and marginal deficiency and anemia were 17.2% (95% CI: 14.2%, 20.6%), 33.2% (95% CI: 29.6%, 37.1%), and 22.7% (95% CI: 19.5%, 26.2%), respectively. The adjusted geometric means of the RBC folate concentration increased significantly (P-trend < 0.001) in WCBA who had normal vitamin B-12 status relative to WCBA who were vitamin B-12 deficient.Conclusions: In Belize, the prevalence of folate and vitamin B-12 deficiencies continues to be a public health concern among WCBA. Furthermore, low folate status co-occurred with low vitamin B-12 status, underlining the importance of providing adequate vitamin B-12 and folic acid intake through approaches such as mandatory food fortification.

Possible effects of neonatal vitamin B12 status on TSH-screening program: a cross-sectional study from Turkey

BACKGROUND

In this study we evaluated whether vitamin B12 deficiency affects neonatal screening (NS) for congenital hypothyroidism (CH).

METHODS

A cross-sectional study conducted from 2010 to 2011. A total of 10,740 infants were born in our hospital in this period. Thyroid-stimulating hormone (TSH) was tested for NS and neonates with abnormal screening results (TSH>20 mIU/L) were re-examined. Two hundred and twenty-nine re-called subjects (re-call rate 2.3%) were compared to 77 randomly selected newborns with normal TSH screening among these term newborns in terms of serum TSH, free T4, vitamin B12 and homocysteine status.

RESULTS

Of the 229 re-called subjects, 11 infants with CH and 21 infants with transient TSH elevation were detected. In the normal TSH screening group, only two infants were diagnosed with transient TSH elevation. Mean serum B12 levels were 126.4±48.7 pg/mL and 211.9±127.9 pg/mL in the positive TSH-screening group and the control group, respectively. There was a significant difference between positive and normal TSH-screening groups in regard to serum TSH, free T4, serum B12 and homocysteine levels.

CONCLUSIONS

We found a significant vitamin B12 deficiency in positive TSH-screening infants. Beside the crucial role of vitamin B12 in newborns, deficiency seems to increase the recall rates of infants in an NS program for CH.

Dietary modulation of cortical excitation and inhibition

The balance of excitatory and inhibitory neurotransmitters in the brain affects both neural responses and behaviour in humans and animals. Here we investigated whether dietary intervention aimed at increasing levels of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) can influence neural responses to basic sensory stimuli. Using a steady-state electroencephalography (EEG) paradigm, we found that the neural response to visual patterns was reduced in individuals who consumed a yeast extract product rich in substances associated with the production of GABA (glutamate and B vitamins), but not in a control group who consumed a placebo substance ( n = 14 per group). This demonstrates that the balance of excitation and inhibition in the brain can be influenced by dietary interventions, suggesting possible clinical benefits in conditions (e.g. epilepsy) where inhibition is abnormal.

Vitamin B12 status in pregnant women and their infants in South India

BACKGROUND/OBJECTIVES

Vitamin B₁₂ deficiency during pregnancy has been associated with increased risk of adverse perinatal outcomes. However, few studies have investigated the burden and determinants of vitamin B₁₂ status in young infants. This study was conducted to determine the associations between maternal and infant vitamin B₁₂ status.

SUBJECTS/METHODS

Pregnant women participating in a vitamin B₁₂ supplementation trial in Bangalore, India, were randomized to receive vitamin B₁₂ (50 μg) or placebo supplementation daily during pregnancy through 6 weeks postpartum. All women received 60 mg of iron and 500 μg of folic acid daily during pregnancy, as per standard of care. This prospective analysis was conducted to determine the associations between maternal vitamin B₁₂ biomarkers (that is, plasma vitamin B₁₂, methylmalonic acid (MMA) and tHcy) during each trimester with infant vitamin B₁₂ status (n=77) at 6 weeks of age.

RESULTS

At baseline (⩽14 weeks of gestation), 51% of mothers were vitamin B₁₂ deficient (vitamin B₁₂<150 pmol/l) and 43% had impaired vitamin B₁₂ status (vitamin B₁₂<150 pmol/l and MMA>0.26 μmol/l); 44% of infants were vitamin B₁₂ deficient at 6 weeks of age. After adjusting for vitamin B₁₂ supplementation, higher vitamin B₁₂ concentrations in each trimester were associated with increased infant vitamin B₁₂ concentrations and lower risk of vitamin B₁₂ deficiency in infants (P<0.05). After adjusting for vitamin B₁₂ supplementation, infants born to women with vitamin B₁₂ deficiency had a twofold greater risk of vitamin B₁₂ deficiency (P<0.01). Higher maternal folate concentrations also predicted lower risk of vitamin B₁₂ deficiency in infants (P<0.05). Impaired maternal vitamin B₁₂ status, which combined both circulating and functional biomarkers, was the single best predictor of infant vitamin B₁₂ status.

CONCLUSIONS

Impaired maternal vitamin B₁₂ status throughout pregnancy predicted higher risk of vitamin B₁₂ deficiency in infants, after adjusting for vitamin B₁₂ supplementation. Future interventions are needed to improve vitamin B₁₂ status periconceptionally, and to ensure optimal vitamin B₁₂ status and health outcomes in pregnant women and their children.

Correlation between maternal and childhood VitB12, folic acid and ferritin levels

OBJECTIVE

To determine the correlation between serum folic acid, vitamin B12 and ferritin of mother and child and to study various neonatal risk factors as a cause of anemia in children.

METHODS

One hundred eighty children two months to two years of age admitted in the department of Pediatric Medicine of The Children's Hospital and The Institute of Child Health Lahore from January 2013 to January 2015 with common medical conditions having anemia were included. Complete blood count (CBC), serum ferritin level, folic acid and Vitamin (Vit) B12 level were sent of children and their mothers. Data was analyzed using SPSS version 20.

RESULTS

Out of 180 children with anemia, 66.7% were males. Mean age of children was 7.3months. Fifty-five percent children were malnourished according to z scoring. The mean Hemoglobin (Hb) of children was 8 g/dl. Only 4% children had low ferritin level while 60% had low folic acid and 45% had decreased VitB12. There was significant correlation between Hb of mother and child (p =0.02), Vit B12 deficiency (p=0.008) and iron deficiency (p<0.001). Premature children had lower folic acid levels (p =0.02), while prematurity, IUGR, previous admission and history of sepsis showed no association with anemia in our study. Both breast-feeding and top feeding showed significant association with anemia with p-value of 0.042 and 0.003 respectively while dilution showed no impact on anemia.

CONCLUSION

Maternal anemia has a significant impact on child's hemoglobin. As compared to previous concept of increased iron deficiency in children we found increased occurrence of folic acid and VitB12 deficiency in children and their mothers.

Correlations between Maternal, Breast Milk, and Infant Vitamin B12 Concentrations among Mother-Infant Dyads in Vancouver, Canada and Prey Veng, Cambodia: An Exploratory Analysis

Vitamin B12 plays an essential role in fetal and infant development. In regions where animal source food consumption is low and perinatal supplementation is uncommon, infants are at risk of vitamin B12 deficiency. In this secondary analysis, we measured total vitamin B12 concentrations in maternal and infant serum/plasma and breast milk among two samples of mother-infant dyads in Canada (assessed at 8 weeks post-partum) and in Cambodia (assessed between 3-27 weeks post-partum). Canadian mothers (n = 124) consumed a daily vitamin B12-containing multiple micronutrient supplement throughout pregnancy and lactation; Cambodian mothers (n = 69) were unsupplemented. The maternal, milk, and infant total vitamin B12 concentrations (as geometric means (95% CI) in pmol/L) were as follows: in Canada, 698 (648,747), 452 (400, 504), and 506 (459, 552); in Cambodia, 620 (552, 687), 317 (256, 378), and 357 (312, 402). The majority of participants were vitamin B12 sufficient (serum/plasma total B12 > 221 pmol/L): 99% and 97% of mothers and 94% and 84% of infants in Canada and Cambodia, respectively. Among the Canadians, maternal, milk, and infant vitamin B12 were all correlated (p < 0.05); only maternal and infant vitamin B12 were correlated among the Cambodians (p < 0.001).

Vitamin B12 Intake and Related Biomarkers: Associations in a Dutch Elderly Population

BACKGROUND

Vitamin B12 status is measured by four plasma/ serum biomarkers: total vitamin B12 (total B12), holotranscobalamin (holoTC), methylmalonic acid (MMA) and homocysteine (tHcy). Associations of B12 intake with holoTC and tHcy and associations between all four biomarkers have not been extensively studied. A better insight in these associations may contribute to an improved differentiation between vitamin B12 deficiency and a normal vitamin B12 status.

OBJECTIVE

This study investigates associations between vitamin B12 intake and biomarkers and associations between biomarkers.

DESIGN

In this cross-sectional observational study, levels of total B12, HoloTC, MMA and tHcy were determined in participants of the B-PROOF study: 2919 elderly people (≥65 years, with a mean age of 74.1 years, a mean BMI of 27.1 and 50% women) with elevated tHcy levels (≥12 µmol/L). B12 intake was assessed in a subsample. We assessed the association between intake and status with multivariate regression analysis. We explored the dose-response association between B12 intake and biomarkers and the association of total B12 and holoTC with tHcy and MMA with restricted cubic spline plots.

RESULTS

A doubling of B12 intake was associated with 9% higher total B12, 15% higher HoloTC, 9% lower MMA and 2% lower tHcy. Saturation of biomarkers occurs with dietary intakes of >5 μg B12. Spline regression showed that levels of MMA and tHcy started to rise when vitamin B12 levels fall below 330 pmol/L and with HoloTC levels below 100 pmol/L, with a sharp increase with levels of B12 and HoloTC below 220 and 50 pmol/L respectively.

CONCLUSIONS

In this study we observed a significant association between vitamin B12 intake and vitamin B12 biomarkers and between the biomarkers. The observed inflections for total B12 and holoTC with MMA and tHcy could indicate cut-off levels for further testing for B12 deficiency and determining subclinical B12 deficiency.

B12 deficiency is common in infants and is accompanied by serious neurological symptoms

AIM

Adverse neurological symptoms have been linked to vitamin B12 deficiency in infants. This explorative study described the clinical presentation associated with vitamin B12 deficiency in this age group.

METHODS

The study comprised infants who were born between 2004 and 2012 and were tested for vitamin B12 levels after they were admitted to a hospital with neurological symptoms at less than one year of age. Vitamin B12 deficiency was defined as low cobalamin in serum and/or increased homocysteine and/or increased methylmalonate. It was diagnosed according to the applicable International Classification of Diseases, 10th revision, and recorded as vitamin B12 deficiency in the medical records. All information was retrieved from medical records and compared to symptomatic infants with normal levels.

RESULTS

Of the 121 infants tested, 35 had vitamin B12 deficiency and 86 had normal levels. Vitamin B12 deficiency was diagnosed at an average age of 1.7 months and was more common among boys. Seizures and apparent life-threatening events were the most common symptoms among infants with B12 deficiency compared to infants with normal levels.

CONCLUSION

Vitamin B12 deficiency was more common in infants than we expected and presented with severe symptoms, such as seizures and apparent life-threatening events.

Analyzing B-vitamins in Human Milk: Methodological Approaches

According to the World Health Organization (WHO), infants should be exclusively breastfed for the first six months of life. However, there is insufficient information about the concentration of nutrients in human milk. For some nutrients, including B-vitamins, maternal intake affects their concentration in human milk but the extent to which inadequate maternal diets affect milk B-vitamin content is poorly documented. Little is known about infant requirements for B-vitamins; recommendations are generally set as Adequate Intakes (AI) calculated on the basis of the mean volume of milk (0.78 L/day) consumed by infants exclusively fed with human milk from well-nourished mothers during the first six months, and the concentration of each vitamin in milk based on reported values. Methods used for analyzing B-vitamins, commonly microbiological, radioisotope dilution or more recently chromatographic, coupled with UV, fluorometric and MS detection, have rarely been validated for the complex human milk matrix. Thus the validity, accuracy, and sensitivity of analytical methods is important for understanding infant requirements for these nutrients, the maternal intakes needed to support adequate concentrations in breast milk. This review summarizes current knowledge on methods used for analyzing the B-vitamins thiamin, riboflavin, niacin, vitamin B-6 and pantothenic acid, vitamin B-12, folate, biotin, and choline in human milk, their chemical and physical properties, the different forms and changes in concentration during lactation, and the effects of deficiency on the infant.

Vitamin B12 among Vegetarians: Status, Assessment and Supplementation

Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism.

Effects of Two-Year Vitamin B12 and Folic Acid Supplementation on Depressive Symptoms and Quality of Life in Older Adults with Elevated Homocysteine Concentrations: Additional Results from the B-PROOF Study, an RCT

Lowering elevated plasma homocysteine (Hcy) concentrations by supplementing vitamin B₁₂ and folic acid may reduce depressive symptoms and improve health-related quality of life (HR-QoL) in older adults. This study aimed to test this hypothesis in a randomized controlled trial. Participants (N = 2919, ≥65 years, Hcy concentrations ≥12 µmol/L) received either 500 µg vitamin B₁₂ and 400 µg folic acid daily or placebo for two years. Both tablets contained 15 µg vitamin D₃. Depressive symptoms were measured with the Geriatric Depression Scale-15 (GDS-15). HR-QoL was assessed with the SF-12 Mental and Physical component summary scores and the EQ-5D Index score and Visual Analogue Scale. Differences in two-year change scores were analyzed with Analysis of Covariance (ANCOVA). Hcy concentrations decreased more in the intervention group, but two-year change scores of the GDS-15 and three of four HR-QoL measures did not differ between groups. The EQ-5D Index score declined less in the intervention group than in the placebo group (mean change 0.00 vs. −0.02, p = 0.004). In conclusion, two-year supplementation with vitamin B₁₂ and folic acid in older adults with hyperhomocysteinemia showed that lowering Hcy concentrations does not reduce depressive symptoms, but it may have a small positive effect on HR-QoL.

Causes, Consequences and Public Health Implications of Low B-Vitamin Status in Ageing

The potential protective roles of folate and the metabolically related B-vitamins (vitamins B12, B6 and riboflavin) in diseases of ageing are of increasing research interest. The most common cause of folate and riboflavin deficiencies in older people is low dietary intake, whereas low B12 status is primarily associated with food-bound malabsorption, while sub-optimal vitamin B6 status is attributed to increased requirements in ageing. Observational evidence links low status of folate and the related B-vitamins (and/or elevated concentrations of homocysteine) with a higher risk of degenerative diseases including cardiovascular disease (CVD), cognitive dysfunction and osteoporosis. Deficient or low status of these B-vitamins alone or in combination with genetic polymorphisms, including the common MTHFR 677 C → T polymorphism, could contribute to greater disease risk in ageing by causing perturbations in one carbon metabolism. Moreover, interventions with the relevant B-vitamins to optimise status may have beneficial effects in preventing degenerative diseases. The precise mechanisms are unknown but many have been proposed involving the role of folate and the related B-vitamins as co-factors for one-carbon transfer reactions, which are fundamental for DNA and RNA biosynthesis and the maintenance of methylation reactions. This review will examine the evidence linking folate and related B-vitamins with health and disease in ageing, associated mechanisms and public health implications.

Oral absorption of peptides and nanoparticles across the human intestine: Opportunities, limitations and studies in human tissues

In this contribution, we review the molecular and physiological barriers to oral delivery of peptides and nanoparticles. We discuss the opportunities and predictivity of various in vitro systems with special emphasis on human intestine in Ussing chambers. First, the molecular constraints to peptide absorption are discussed. Then the physiological barriers to peptide delivery are examined. These include the gastric and intestinal environment, the mucus barrier, tight junctions between epithelial cells, the enterocytes of the intestinal epithelium, and the subepithelial tissue. Recent data from human proteome studies are used to provide information about the protein expression profiles of the different physiological barriers to peptide and nanoparticle absorption. Strategies that have been employed to increase peptide absorption across each of the barriers are discussed. Special consideration is given to attempts at utilizing endogenous transcytotic pathways. To reliably translate in vitro data on peptide or nanoparticle permeability to the in vivo situation in a human subject, the in vitro experimental system needs to realistically capture the central aspects of the mentioned barriers. Therefore, characteristics of common in vitro cell culture systems are discussed and compared to those of human intestinal tissues. Attempts to use the cell and tissue models for in vitro-in vivo extrapolation are reviewed.

Nutritional and Micronutrient Status of Female Workers in a Garment Factory in Cambodia

Background: Concerns about the nutritional status of Cambodian garment workers were raised years ago but data are still scarce. The objectives of this study are to examine the nutritional, hemoglobin and micronutrient status of female workers in a garment factory in Phnom Penh, Cambodia, and to assess if body mass index is associated with hemoglobin and/or micronutrient status. Methods: A cross-sectional survey was conducted among 223 female workers (nulliparous, non-pregnant) at a garment factory in Phnom Penh. Anthropometric measurements were performed and blood samples were taken to obtain results on hemoglobin, iron, vitamin A, vitamin B12 and inflammation status (hemoglobinopathies not determined). Bivariate correlations were used to assess associations. Results: Overall, 31.4% of workers were underweight, 26.9% showed anemia, 22.1% showed iron deficiency, while 46.5% had marginal iron stores. No evidence of vitamin A or vitamin B12 deficiency was found. Body mass index was associated with serum ferritin (negative) and serum retinol-binding protein (positive) concentrations, but not strongly. A comparison between underweight and not underweight workers resulted in distinctions for iron deficiency and iron deficiency anemia, with a higher prevalence among not underweight. Conclusions: The prevalence of underweight, anemia and poor iron status was high. Young and nulliparous female garment workers in Cambodia might constitute a group with elevated risk for nutritional deficiencies. Strategies need to be developed for improving their nutritional, micronutrient and health status. The poor iron status seems to contribute to the overall prevalence of anemia. Low hemoglobin and iron deficiency affected both underweight and those not underweight. Despite the fact that body mass index was negatively associated with iron stores, true differences in iron status between underweight and not underweight participants cannot be confirmed.

Proton-pump inhibitor therapy and vitamin B12 status in an inpatient hospital setting

The risk for impaired vitamin B₁₂ status increases with age, as does the use of proton pump inhibitors (PPI). Long-term use of PPIs is associated with several nutritional deficiencies including B₁₂. Currently, there are no recommendations for B₁₂ screening among patients taking PPIs. Data were abstracted on B₁₂ concentrations, B₁₂-containing supplement use, medications, and select hematological values from a retrospective chart review of 658 adults, 391 with serum B₁₂ concentrations, admitted to 6 different medical units at 2 regional hospitals in Southwestern Ontario between 2010 and 2012. We found no difference between PPI users and nonusers and serum B₁₂ concentrations (404 ± 224 vs 369 ± 213 pmol/L; P = 0.0690). This may be due to use of B₁₂ containing multivitamins in 41% of PPI users. Regression modelling found that aging increases the odds of having an impaired B₁₂ status (<220 pmol/L) by 1.4 times and those using B₁₂ supplements are almost 4 times more likely to have an impaired status. Mean corpuscular volume was not related to B₁₂ status. In this population, older PPI users are more likely to be using multivitamins, which may delay nutritional deficiencies. However, the lower B₁₂ concentrations of PPI users taking only B₁₂ supplements is a concern and requires further research. Finally, physicians need to be aware that mean corpuscular volume is no longer recommended as an effective biomarker for B₁₂ screening and updated screening protocols need to be used to reduce the possibility of adverse neurological effects from impaired B₁₂ status.

Oral Vitamin B12 Replacement for the Treatment of Pernicious Anemia

Many patients with pernicious anemia are treated with lifelong intramuscular (IM) vitamin B12 replacement. As early as the 1950s, there were studies suggesting that oral vitamin B12 replacement may provide adequate absorption. Nevertheless, oral vitamin B12 replacement in patients with pernicious anemia remains uncommon in clinical practice. The objective of this review is to provide an update on the effectiveness of oral vitamin B12 for the treatment of pernicious anemia, the recommended dosage, and the required frequency of laboratory test and clinical monitoring. Relevant articles were identified by PubMed search from January 1, 1980 to March 31, 2016 and through hand search of relevant reference articles. Two randomized controlled trials, three prospective papers, one systematic review, and three clinical reviews fulfilled our inclusion criteria. We found that oral vitamin B12 replacement at 1000 μg daily was adequate to replace vitamin B12 levels in patients with pernicious anemia. We conclude that oral vitamin B12 is an effective alternative to vitamin B12 IM injections. Patients should be offered this alternative after an informed discussion on the advantages and disadvantages of both treatment options.

Pernicious Anemia with Autoimmune Hemolytic Anemia: A Case Report and Literature Review

Pernicious anemia is a common cause of vitamin B12 deficiency. Here, we discuss a case of a young woman who presented with severe anemia along with a history of iron deficiency anemia. After a review of her clinical presentation and laboratory data, we identified an autoimmune hemolytic anemia and a concomitant pernicious anemia. The concurrence of both these hematological diagnoses in a patient is rare.

Vitamin B12 and placental expression of transcobalamin in pregnant adolescents

BACKGROUND

Transcobalamin is a key placental protein involved in transport of vitamin B12 to the fetus. However, few data currently exist on the ability of the placenta to modify vitamin B12 transporter expression, particularly in high-risk populations such as pregnant adolescents.

OBJECTIVE

This study was conducted to determine the impact of maternal and neonatal serum vitamin B12 concentrations on placental transcobalamin (TC) expression in a cohort of healthy pregnant adolescents in the United States.

DESIGN

Serum vitamin B12 concentrations were measured in maternal blood samples at mid-gestation (26.4 ± 2.8 weeks) and delivery (39.8 ± 1.4 weeks) and infant cord blood samples at birth. Placentas were collected at delivery and TC mRNA expression (ΔΔCt) and TC protein abundance (TC:α-actin) were evaluated. Linear and binomial regression models were used to examine the associations of maternal serum (mid-gestation, delivery) and cord blood vitamin B12 concentrations with placental TC mRNA expression and protein abundance (n = 63).

RESULTS

Maternal serum vitamin B12 concentrations at mid-gestation or delivery were not significantly associated with placental TC mRNA expression or TC protein abundance (p > 0.05). Higher placental TC protein abundance was associated with increased cord blood vitamin B12 concentrations (p = 0.003).

CONCLUSIONS

Higher placental TC protein abundance was associated with higher cord blood vitamin B12 concentrations, suggesting a potential role in vitamin B12 transport to the fetus.

Biomarkers and Algorithms for the Diagnosis of Vitamin B12 Deficiency

Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In conjunction with total B12 and its bioactive protein-bound form, holo-transcobalamin (holo-TC), Hcy, and MMA are the preferred serum biomarkers utilized to determine B12 status. Clinically, vitamin B12 deficiency leads to neurological deterioration and megaloblastic anemia, and, if left untreated, to death. Subclinical vitamin B12 deficiency (usually defined as a total serum B12 of <200 pmol/L) presents asymptomatically or with rather subtle generic symptoms that oftentimes are mistakenly ascribed to unrelated disorders. Numerous studies have now established that serum vitamin B12 has limited diagnostic value as a stand-alone marker. Low serum levels of vitamin B12 not always represent deficiency, and likewise, severe functional deficiency of the micronutrient has been documented in the presence of normal and even high levels of serum vitamin B12. This review discusses the usefulness and limitations of current biomarkers of B12 status in newborn screening, infant and adult diagnostics, the algorithms utilized to diagnose B12 deficiency and unusual findings of vitamin B12 status in various human disorders.

Canadian Consensus on Female Nutrition: Adolescence, Reproduction, Menopause, and Beyond

OBJECTIVES

To provide health care professionals in Canada with the basic knowledge and tools to provide nutrition guidance to women through their lifecycle.

OUTCOMES

Optimal nutrition through the female lifecycle was evaluated, with specific focus on adolescence, pre-conception, pregnancy, postpartum, menopause, and beyond. The guideline begins with an overview of guidance for all women, followed by chapters that examine the evidence and provide recommendations for the promotion of healthy nutrition and body weight at each life stage. Nutrients of special concern and other considerations unique to each life stage are discussed in each chapter.

EVIDENCE

Published literature, governmental and health agency reports, clinical practice guidelines, grey literature, and textbook sources were used in supporting the recommendations made in this document.

VALUES

The quality of evidence was rated using the criteria described in the report of the Canadian Task Force on Preventive Health Care. CHAPTER 2: GENERAL FEMALE NUTRITION: Summary Statements Recommendations CHAPTER 3: ADOLESCENCE NUTRITION: Summary Statements Recommendations CHAPTER 4: PRE-CONCEPTUAL NUTRITION: Summary Statement Recommendations CHAPTER 5: NUTRITION IN PREGNANCY: Summary Statements Recommendations CHAPTER 6: POSTPARTUM NUTRITION AND LACTATION: Summary Statements Recommendations CHAPTER 7: NUTRITION DURING MENOPAUSE AND BEYOND: Summary Statement Recommendations.

Cutaneous Hyperpigmentation in Megaloblastic Anemia: a Five Year Retrospective Review

Background

Cutaneous hyperpigmentation is an often overlooked clinical sign in megaloblastic anemia (MA) which has been sporadically reported in the literature.

Methods

We describe the bone marrow (BM) changes and clinicolaboratory characteristics of 25 of 198 adult cases (>16 years) with cutaneous hyperpigmentation who underwent BM evaluation for cytopenia (s).

Results

Twenty-one of 25 cases (84%) had MA, while MA without hyperpigmentation occurred only in 12 of remainder 173 cases (P<0.001). Knuckle pad hyperpigmentation (KP) was noted in 16 (64%) cases; whereas 9 (36%) had diffuse brownish black discoloration (DP) of the palms and/or soles. Eighteen of 25 (72%) cases had pancytopenia (13 with KP) and 7 of 25 (28%) had bicytopenia (3 with KP). In addition, five cases (20%) presented with pyrexia. Of the 17 cases where data available, eleven were B₁₂ deficient [<190 pg/ml; eight had severe deficiency (<100 pg/ml); ref.; 190–800pg/ml], while 4 had pure folate deficiency (< 4.0 ng/ml; ref.; 4–20ng/ml); and remainder 2 had combined B₁₂ and folate deficiency. Compared to those with diffuse pigmentation; KP group had lower Hb (69.6 ± 24.2 vs. 86.3 ± 33.9 g/L), higher MCV (106.1 ±12.6 vs. 99.2 ± 7.6 fL), lower platelet count (50.9 ± 29.3 vs. 69.6 ± 36.5 × 10⁹/L), and lower median B₁₂ [100.0 (30.0 – 822.0) vs. 316.0 (142.0 – 1617.3) pg/ml] (P>0.05). In six cases where follow-up data were available, there was a significant reversal of hyperpigmentation at 12 weeks following parenteral cobalamin therapy. In all five cases with pyrexia, fever subsided after 24 to 72 hours following administration of parenteral cobalamin therapy.

Conclusion

Cutaneous hyperpigmentation and cytopenia (s) are strongly associated with megaloblastic anemia. Knuckle pad hyperpigmentation is much more frequent than diffuse pigmentation of the palms and/or soles in such patents. A nonsignificant trend towards a greater degree of MA was found in cases with pigmentation of the knuckles.

The Pediatric Methionine Requirement Should Incorporate Remethylation Potential and Transmethylation Demands

The metabolic demand for methionine is great in neonates. Indeed, methionine is the only indispensable sulfur amino acid and is required not only for protein synthesis and growth but is also partitioned to a greater extent to transsulfuration for cysteine and taurine synthesis and to >50 transmethylation reactions that serve to methylate DNA and synthesize metabolites, including creatine and phosphatidylcholine. Therefore, the pediatric methionine requirement must accommodate the demands of rapid protein turnover as well as vast nonprotein demands. Because cysteine spares the methionine requirement, it is likely that the dietary provision of transmethylation products can also feasibly spare methionine. However, understanding the requirement of methionine is further complicated because demethylated methionine can be remethylated by the dietary methyl donors folate and betaine (derived from choline). Intakes of dietary methyl donors are highly variable, which is of particular concern for newborns. It has been demonstrated that many populations have enhanced requirements for these nutrients, and nutrient fortification may exacerbate this phenomenon by selecting phenotypes that increase methyl requirements. Moreover, higher transmethylation rates can limit methyl supply and affect other transmethylation reactions as well as protein synthesis. Therefore, careful investigations are needed to determine how remethylation and transmethylation contribute to the methionine requirement. The purpose of this review is to support our hypothesis that dietary methyl donors and consumers can drive methionine availability for protein synthesis and transmethylation reactions. We argue that nutritional strategies in neonates need to ensure that methionine is available to meet requirements for growth as well as for transmethylation products.

A Common Polymorphism in HIBCH Influences Methylmalonic Acid Concentrations in Blood Independently of Cobalamin

Methylmalonic acid (MMA) is a by-product of propionic acid metabolism through the vitamin B12 (cobalamin)-dependent enzyme methylmalonyl CoA mutase. Elevated MMA concentrations are a hallmark of several inborn errors of metabolism and indicators of cobalamin deficiency in older persons. In a genome-wide analysis of 2,210 healthy young Irish adults (median age 22 years) we identified a strong association of plasma MMA with SNPs in 3-hydroxyisobutyryl-CoA hydrolase (HIBCH, p = 8.42 × 10(-89)) and acyl-CoA synthetase family member 3 (ACSF3, p = 3.48 × 10(-19)). These loci accounted for 12% of the variance in MMA concentration. The most strongly associated SNP (HIBCH rs291466; c:2T>C) causes a missense change of the initiator methionine codon (minor-allele frequency = 0.43) to threonine. Surprisingly, the resulting variant, p.Met1?, is associated with increased expression of HIBCH mRNA and encoded protein. These homozygotes had, on average, 46% higher MMA concentrations than methionine-encoding homozygotes in young adults with generally low MMA concentrations (0.17 [0.14-0.21] μmol/L; median [25(th)-75(th) quartile]). The association between MMA levels and HIBCH rs291466 was highly significant in a replication cohort of 1,481 older individuals (median age 79 years) with elevated plasma MMA concentrations (0.34 [0.24-0.51] μmol/L; p = 4.0 × 10(-26)). In a longitudinal study of 185 pregnant women and their newborns, the association of this SNP remained significant across the gestational trimesters and in newborns. HIBCH is unique to valine catabolism. Studies evaluating flux through the valine catabolic pathway in humans should account for these variants. Furthermore, this SNP could help resolve equivocal clinical tests where plasma MMA values have been used to diagnose cobalamin deficiency.

Vitamin B-12 Concentrations in Breast Milk Are Low and Are Not Associated with Reported Household Hunger, Recent Animal-Source Food, or Vitamin B-12 Intake in Women in Rural Kenya

BACKGROUND

Breast milk vitamin B-12 concentration may be inadequate in regions in which animal-source food consumption is low or infrequent. Vitamin B-12 deficiency causes megaloblastic anemia and impairs growth and development in children.

OBJECTIVE

We measured vitamin B-12 in breast milk and examined its associations with household hunger, recent animal-source food consumption, and vitamin B-12 intake.

METHODS

In a cross-sectional substudy nested within a cluster-randomized trial assessing water, sanitation, hygiene, and nutrition interventions in Kenya, we sampled 286 women 1-6 mo postpartum. Mothers hand-expressed breast milk 1 min into a feeding after 90 min observed nonbreastfeeding. The Household Hunger Scale was used to measure hunger, food intake in the previous week was measured with the use of a food-frequency questionnaire (FFQ), and vitamin B-12 intake was estimated by using 24-h dietary recall. An animal-source food score was based on 10 items from the FFQ (range: 0-70). Breast milk vitamin B-12 concentration was measured with the use of a solid-phase competitive chemiluminescent enzyme immunoassay and was modeled with linear regression. Generalized estimating equations were used to account for correlated observations at the cluster level.

RESULTS

Median (IQR) vitamin B-12 intake was 1.5 μg/d (0.3, 9.7 μg/d), and 60% of women consumed <2.4 μg/d, the estimated average requirement during lactation. Median (IQR) breast milk vitamin B-12 concentration was 113 pmol/L (61, 199 pmol/L); 89% had concentrations <310 pmol/L, the estimated adequate concentration. Moderate or severe hunger prevalence was 27%; the animal-source food score ranged from 0 to 30 item-d/wk. Hunger and recent animal-source food and vitamin B-12 intake were not associated with breast milk vitamin B-12 concentrations. Maternal age was negatively associated with breast milk vitamin B-12 concentrations.

CONCLUSION

Most lactating Kenyan women consumed less than the estimated average requirement of vitamin B-12 and had low breast milk vitamin B-12 concentrations. We recommend interventions that improve vitamin B-12 intake in lactating Kenyan women to foster maternal health and child development. The main trial was registered at clinicaltrials.gov as NCT01704105.

Association between metformin and vitamin B12 deficiency in patients with type 2 diabetes: A systematic review and meta-analysis

AIM

Metformin is the most widely used oral hypoglycaemic drug, but it may lower B₁₂ status, which could have important clinical implications. We undertook a systematic review and meta-analysis of the relationship between metformin use and vitamin B₁₂ deficiency in persons with type 2 diabetes.

METHODS

Electronic database searches were undertaken (1st January 1957-1st July 2013) using the Cochrane library, Scopus, CINAHL, Grey literature databases, Pub Med Central, NICE Clinical Guidelines UK, and ongoing clinical trials. Included studies were of any study design, with data from patients with type 2 diabetes of any age or gender, taking any dose or duration of metformin. Planned primary outcomes were serum vitamin B₁₂ levels, % prevalence or incidence of vitamin B₁₂ deficiency and risk of vitamin B₁₂ deficiency.

RESULTS

Twenty-six papers were included in the review. Ten out of 17 observational studies showed statistically significantly lower levels of vitamin B₁₂ in patients on metformin than not on metformin. Meta-analysis performed on four trials demonstrated a statistically significant overall mean B₁₂ reducing effect of metformin of 57pmol/L [WMD (fixed)=-0.57 (95% CI: -35 to -79pmol/L)] after 6weeks to 3months of use.

CONCLUSION

The evidence from this review demonstrates an association between metformin usage and lower levels of vitamin B₁₂ by 57pmol/L, which leads to frank deficiency or borderline status in some patients with type 2 diabetes. This suggests that it is prudent to monitor B₁₂ levels in these patients who are at increased risk of deficiency.

Folate and Vitamin B12 Deficiency Among Non-pregnant Women of Childbearing-Age in Guatemala 2009-2010: Prevalence and Identification of Vulnerable Populations

INTRODUCTION

Information on folate and vitamin B12 deficiency rates in Guatemala is essential to evaluate the current fortification program. The objectives of this study were to describe the prevalence of folate and vitamin B12 deficiencies among women of childbearing age (WCBA) in Guatemala and to identify vulnerable populations at greater risk for nutrient deficiency.

METHODS

A multistage cluster probability study was designed with national and regional representation of nonpregnant WCBA (15-49 years of age). Primary data collection was carried out in 2009-2010. Demographic and health information was collected through face-to-face interviews. Blood samples were collected from 1473 WCBA for serum and red blood cell (RBC) folate and serum vitamin B12. Biochemical concentrations were normalized using geometric means. Prevalence rate ratios were estimated to assess relative differences among different socioeconomic and cultural groups including ethnicity, age, education level, wealth index and rural versus urban locality.

RESULTS

National prevalence estimates for deficient serum [<10 nmol per liter (nmol/L)] and RBC folate (<340 nmol/L) concentrations were 5.1 % (95 % CI 3.8, 6.4) and 8.9 % (95 % CI 6.7, 11.7), respectively; for vitamin B12 deficiency (<148 pmol/L) 18.5 % (95 % CI 15.6, 21.3). Serum and RBC folate deficiency prevalences were higher for rural areas than for urban areas (8.0 vs. 2.0 % and 13.5 vs. 3.9 %, respectively). The prevalence of RBC folate deficiency showed wide variation by geographic region (3.2-24.9 %) and by wealth index (4.1-15.1 %). The prevalence of vitamin B12 deficiency also varied among regions (12.3-26.1 %).

CONCLUSIONS

In Guatemala, folate deficiency was more prevalent among indigenous rural and urban poor populations. Vitamin B12 deficiency was widespread among WCBA. Our results suggest the ongoing need to monitor existing fortification programs, in particular regarding its reach to vulnerable populations.

Vitamin B-12 concentration, memory performance, and hippocampal structure in patients with mild cognitive impairment

BACKGROUND

Low-normal concentrations of vitamin B-12 (VitB12) may be associated with worse cognition. However, previous evidence has been mixed, and the underlying mechanisms remain unclear.

OBJECTIVE

We determined whether serum VitB12 concentrations within the normal range were linked to memory functions and related neuronal structures in patients with mild cognitive impairment (MCI).

DESIGN

In a cross-sectional design, we assessed 100 amnestic MCI patients (52 women; age range: 50-80 y) with low- and high-normal VitB12 concentration (median split: 304 pmol/L) for memory functions with the use of the Auditory Verbal Learning Test. MRI was performed at 3 tesla (n= 86) for the estimation of the volume and microstructure of the hippocampus and its subfields as indicated by the mean diffusivity on diffusion-weighted images. With the use of a mediation analysis, we examined whether the relation between VitB12 and memory performance was partially explained by volume or microstructure.

RESULTS

MCI patients with low-normal VitB12 showed a significantly poorer learning ability (P= 0.014) and recognition performance (P= 0.008) than did patients with high-normal VitB12. Also, the microstructure integrity of the hippocampus was lower in patients with low-normal VitB12, mainly in the cornu ammonis 4 and dentate gyrus region (P= 0.029), which partially mediated the effect of VitB12 on memory performance (32-48%). Adjustments for age, sex, education, apolipoprotein E e4 status, and total homocysteine, folate, and creatinine did not attenuate the effects.

CONCLUSIONS

Low VitB12 concentrations within the normal range are associated with poorer memory performance, which is an effect that is partially mediated by the reduced microstructural integrity of the hippocampus. Future interventional trials are needed to assess whether supplementation of VitB12 may improve cognition in MCI patients even in the absence of clinically manifested VitB12 deficiency. This trial was registered at clinicaltrials.gov as NCT01219244.

Methylmalonic Acid and Homocysteine as Indicators of Vitamin B-12 Deficiency in Cancer

Background/Aims

Normal or high serum vitamin B-12 levels can sometimes be seen in a B-12 deficient state, and can therefore be misleading. High levels of Methymalonic Acid (MMA) and Homocysteine (HC) have been identified as better indicators of B-12 deficiency than the actual serum B-12 level itself. We evaluated the prevalence of vitamin B-12 deficiency using appropriate cut-off levels of vitamin B-12, MMA and HC, and determined the relationship between serum levels of vitamin B-12, MMA and HC in cancer.

Methods

This is a cross-sectional study using a consecutive case series of 316 cancer patients first seen at Cancer Treatment Centers of America^® (CTCA) at Midwestern Regional Medical Center between April 2014 and June 2014. All patients were evaluated at baseline for vitamin B-12 (pg/mL), MMA (nmol/L) and HC (μmol/L) levels. In accordance with previously published research, the following cut-offs were used to define vitamin B-12 deficiency: <300 pg/mL for vitamin B-12, >260 nmol/L for MMA and >12 μmol/L for HC. The relationship between B-12, MMA and HC was evaluated using Spearman's rho correlation coefficient and cross-tabulation analysis. Receiver Operating Characteristic (ROC) curves were estimated using the non-parametric method to further evaluate the diagnostic accuracy of vitamin B-12 using Fedosov quotient as the "gold standard".

Results

Mean age at presentation was 52.5 years. 134 (42.4%) patients were males while 182 (57.6%) were females. Median vitamin B-12, MMA and HC levels were 582.5 pg/mL, 146.5 nmol/L and 8.4 μmol/L respectively. Of 316 patients, 28 (8.9%) were vitamin B-12 deficient based on vitamin B-12 (<300pg/mL), 34 (10.8%) were deficient based on MMA (>260 nmol/L) while 55 (17.4%) were deficient based on HC (>12 μmol/L). Correlation analysis revealed a significant weak negative correlation between vitamin B-12 and MMA (rho = -0.22) as well as B-12 and HC (rho = -0.35). ROC curves suggested MMA to have the best discriminatory power in predicting B-12 deficiency.

Conclusion

Vitamin B-12 is poorly correlated with MMA and HC in cancer. Using serum vitamin B-12 alone to evaluate B-12 status in cancer may fail to identify those with functional deficiency. A thorough clinical assessment is important to identify patients that may have risk factors and/or symptoms suggestive of deficiency. These patients should have additional testing of MMA and HC regardless of their B-12 levels.

A combined supplementation of vitamin B12and omega-3 fatty acids across two generations improves cardiometabolic variables in rats

Our earlier studies indicate that micronutrients (vitamin B₁₂, folic acid) and omega-3 fatty acids especially docosahexaenoic acid (DHA) are interlinked in one carbon cycle.

Neuroregression as an initial manifestation in a toddler with acquired pernicious anaemia

The aetiology spectrum for neuroregression in infants and toddlers is diverse. Vitamin B12 deficiency-mediated neuroregression is less commonly considered as a differential. Prevalence of pernicious anaemia in the general population is 0.1% and is extremely rare in children. We describe a 35-month-old toddler with neuroregression, seizures, coarse tremors, bleating cry and neuropathy. His clinical symptomatology mimicked grey matter degenerative illness and infantile tremor syndrome, a nutritional deficiency-mediated movement disorder. His vitamin B12 level was low and serum homocysteine level was elevated. Haematological manifestations were not overt and anti-intrinsic factor antibody was positive. With parenteral vitamin B12 therapy, there was a dramatic response with clinical and laboratory translation. This report emphasises the need for a high index of suspicion and screening for markers of vitamin B12 deficiency in all children with unexplained acute or subacute neuroregression, seizures and movement disorders as it is potentially reversible.

A novel screening tool (Karanth's test) for vitamin B12 deficiency: a pilot study

BACKGROUND

No practical tests are currently available for screening vitamin B12 deficiency because the available techniques are invasive, expensive, and require a particular level of infrastructure and service that is not available in all places such as rural areas. Thus, we have examined the efficacy of a novel method (Karanth's test) for identifying people with vitamin B12 deficiency as part of a pilot study.

METHODS

An observer-blind study was conducted on 83 consenting patients from a tertiary teaching hospital whose blood was drawn for estimation of serum vitamin B12 over a 2-month period. All of these patients completed the study. In the Karanth's test, the skin color tone is measured at the interphalangeal joint and the phalanx using the Von Luschan skin tone chart. The test result is obtained from differences in the values obtained. This test was performed on the day blood was drawn to measure the serum vitamin B12 levels in the study patients and on every day until discharge for patients tested to be deficient.

RESULTS

Of the 83 patient subjects, 20 showed deficient vitamin B12 levels in the blood test. The Karanth's test readings were significantly different for patients with normal and deficient levels of vitamin B12 (95 % CI, 0.838-2.153). ROC curve analysis suggested that a difference greater than 1.5 should be considered positive. The sensitivity and specificity of the test were determined to be 80 and 84.1 %, respectively. Patients were grouped further according to the Fitzpatrick scale. There were no type I, II or III patients and insufficient IV cases to determine sensitivity and specificity. Sensitivity and specificity were determined to be 57.1 and 94.6 % in type V and 92 and 63.6 % in type VI, respectively. We found that 87 % of our patients who tested positive had normal values on discharge.

CONCLUSION

The Karanth's test is a useful screen for a vitamin B12 deficiency and warrants further evaluation in a larger study population.