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Gastric Damage and Cancer-Associated Biomarkers in Helicobacter pylori-Infected Children. Front Microbiol 2020; 11:90. [PMID: 32117120 PMCID: PMC7029740 DOI: 10.3389/fmicb.2020.00090] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 01/15/2020] [Indexed: 12/11/2022] Open
Abstract
Helicobacter pylori (H. pylori) is well-known to be involved in gastric carcinogenesis, associated with deregulation of cell proliferation and epigenetic changes in cancer-related genes. H. pylori infection is largely acquired during childhood, persisting long-term in about half of infected individuals, a subset of whom will go on to develop peptic ulcer disease and eventually gastric cancer, however, the sequence of events leading to disease is not completely understood. Knowledge on carcinogenesis and gastric damage-related biomarkers is abundant in adult populations, but scarce in children. We performed an extensive literature review focusing on gastric cancer related biomarkers identified in adult populations, which have been detected in children infected with H. pylori. Biomarkers were related to expression levels (RNA or protein) and/or methylation levels (DNA) in gastric tissue or blood of infected children as compared to non-infected controls. In this review, we identified 37 biomarkers of which 24 are over expressed, three are under expressed, and ten genes are significantly hypermethylated in H. pylori-infected children compared to healthy controls in at least 1 study. Only four of these biomarkers (pepsinogen I, pepsinogen II, gastrin, and SLC5A8) have been studied in asymptomatically infected children. Importantly, 13 of these biomarkers (β-catenin, C-MYC, GATA-4, DAPK1, CXCL13, DC-SIGN, TIMP3, EGFR, GRIN2B, PIM2, SLC5A8, CDH1, and VCAM-1.) are consistently deregulated in infected children and in adults with gastric cancer. Future studies should be designed to determine the clinical significance of these changes in infection-associated biomarkers in children and their persistence over time. The effect of eradication therapy over these biomarkers in children if proven significant, could lead to modifications in treatment guidelines for younger populations, and eventually promote the development of preventive strategies, such as vaccination, in the near future.
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Breast milk provides inadequate amounts of vitamin B12 for predominantly breastfed Guatemalan infants. INT J VITAM NUTR RES 2019; 90:395-402. [PMID: 30987548 DOI: 10.1024/0300-9831/a000583] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Vitamin B12 (B12) plays in an important role in the development and function of the brain and nervous system, and adequate B12 status is especially important for the normal development of infants. In previous research conducted in Guatemala City we reported a high prevalence of B12 deficiency in lactating women and their infants 3 and 12 months of age, and low B12 concentrations in breast milk. The objective of this study was to assess predictors of serum B12 concentration in predominantly breastfed Guatemalan infants including intake of B12 from breast milk and other foods. Serum B12, breast milk and other food intakes, anthropometry, morbidity and socioeconomic status were assessed in infants 6.7 ± 0.6 months of age (n = 127, 52% female) in peri-urban Guatemala City. Twenty-four percent of infants had deficient B12 status (serum B12 concentration < 148 pmol/L) and 37% had marginal B12 status (148-220 pmol/L). Serum B12 concentrations were negatively correlated with infants' consumption of energy from breast milk (r = -0.37, p = 0.001), and positively correlated with their total consumption of animal source foods, especially cow's milk (r = 0.40, p = 0.001). Based on previously analyzed breast milk B12 concentrations in a nearby community, breast milk provided < 10% of the recommended daily B12 intake for this age. We conclude that there was a high prevalence of B12 deficiency in these Guatemalan infants by 6 months of age. Serum B12 was higher in infants consuming more cow's milk and lower in those consuming more breast milk.
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Biomarkers of Nutrition for Development (BOND): Vitamin B-12 Review. J Nutr 2018; 148:1995S-2027S. [PMID: 30500928 PMCID: PMC6297555 DOI: 10.1093/jn/nxy201] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/06/2017] [Accepted: 08/02/2018] [Indexed: 12/31/2022] Open
Abstract
This report on vitamin B-12 (B12) is part of the Biomarkers of Nutrition for Development (BOND) Project, which provides state-of-the art information and advice on the selection, use, and interpretation of biomarkers of nutrient exposure, status, and function. As with the other 5 reports in this series, which focused on iodine, folate, zinc, iron, and vitamin A, this B12 report was developed with the assistance of an expert panel (BOND B12 EP) and other experts who provided information during a consultation. The experts reviewed the existing literature in depth in order to consolidate existing relevant information on the biology of B12, including known and possible effects of insufficiency, and available and potential biomarkers of status. Unlike the situation for the other 5 nutrients reviewed during the BOND project, there has been relatively little previous attention paid to B12 status and its biomarkers, so this report is a landmark in terms of the consolidation and interpretation of the available information on B12 nutrition. Historically, most focus has been on diagnosis and treatment of clinical symptoms of B12 deficiency, which result primarily from pernicious anemia or strict vegetarianism. More recently, we have become aware of the high prevalence of B12 insufficiency in populations consuming low amounts of animal-source foods, which can be detected with ≥1 serum biomarker but presents the new challenge of identifying functional consequences that may require public health interventions.
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Abstract
Low cobalamin intake and status during pregnancy or lactation have been linked to adverse maternal and perinatal health outcomes, whereas low cobalamin status during early childhood is associated with impaired development in children. Women who begin pregnancy with depleted stores (low or very low plasma cobalamin) will give birth to depleted infants who are likely to develop deficiency symptoms during the first few weeks or months postpartum. Newly ingested cobalamin during pregnancy and lactation (from diet or supplements) is transferred to the child and is not likely to correct cobalamin status in depleted women. The prevalence of low cobalamin status is high especially in low-income settings or in populations with a low intake of animal products. Folate and cobalamin play interdependent roles in one-carbon metabolism. Although folic acid supplementation during early pregnancy is widely recommended and practiced, cobalamin supplementation during pregnancy and lactation has received little attention. Furthermore, the intake recommendations for pregnant and lactating women and in early life need reevaluation in the light of newly available evidence in the field.
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Abstract
BACKGROUND The purpose of this study was to evaluate the association between vitamin B12 levels and Helicobacter Pylori infection and to examine the clinical usefulness of holotranscobalamin (holoTC) measurement in children. MATERIALS AND METHODS Thirty patients between 6 and 15 years of age, who were diagnosed as H. pylori infected by C(14) urea breath test, and 26 controls were enrolled in the study. Tests for complete blood count, serum vitamin B12 and folate, plasma total homocysteine, and holoTC levels were performed in each patient in the study and control groups. RESULTS Mean plasma holoTC concentrations were significantly lower in children with H. pylori infection before treatment (median 23.7 pmol/L (12.9-37.1 pmol/L)) versus after treatment (median 38.2 pmol/L (21.2-61.4 pmol/L)) and controls (median 36.1 pmol/L (12.6-58.7 pmol/L)). CONCLUSIONS The findings of our study suggest that H. pylori infection has a reversible negative effect on vitamin B12 status reflected in a decreased level of plasma holoTC that normalizes upon treatment of the infection, while no change is observed in total plasma vitamin B12 .
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Contribution of food sources to the vitamin B12 status of South Indian children from a birth cohort recruited in the city of Mysore. Public Health Nutr 2014; 18:596-609. [PMID: 24866058 DOI: 10.1017/s1368980014000974] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE There is evidence that subclinical vitamin B12 (B12) deficiency is common in India. Vegetarianism is prevalent and therefore meat consumption is low. Our objective was to explore the contribution of B12-source foods and maternal B12 status during pregnancy to plasma B12 concentrations. DESIGN Maternal plasma B12 concentrations were measured during pregnancy. Children's dietary intakes and plasma B12 concentrations were measured at age 9.5 years; B12 and total energy intakes were calculated using food composition databases. We used linear regression to examine associations between maternal B12 status and children's intakes of B12 and B12-source foods, and children's plasma B12 concentrations. SETTING South Indian city of Mysore and surrounding rural areas. SUBJECTS Children from the Mysore Parthenon Birth Cohort (n 512, 47.1 % male). RESULTS Three per cent of children were B12 deficient (<150 pmol/l). A further 14 % had 'marginal' B12 concentrations (150-221 pmol/l). Children's total daily B12 intake and consumption frequencies of meat and fish, and micronutrient-enriched beverages were positively associated with plasma B12 concentrations (P=0.006, P=0.01 and P=0.04, respectively, adjusted for socio-economic indicators and maternal B12 status). Maternal pregnancy plasma B12 was associated with children's plasma B12 concentrations, independent of current B12 intakes (P<0.001). Milk and curd (yoghurt) intakes were unrelated to B12 status. CONCLUSIONS Meat and fish are important B12 sources in this population. Micronutrient-enriched beverages appear to be important sources in our cohort, but their high sugar content necessitates care in their recommendation. Improving maternal B12 status in pregnancy may improve Indian children's status.
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Prevalence of anaemia and its associated factors in African children at one and three years residing in the Capricorn District of Limpopo Province, South Africa. Curationis 2014; 37:1160. [DOI: 10.4102/curationis.v37i1.1160] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 07/02/2014] [Accepted: 07/02/2014] [Indexed: 11/01/2022] Open
Abstract
Objective: The present study evaluated the prevalence of anaemia and its determinants in one- and three-year-old children from the Capricorn District of Limpopo Province, South Africa. Methods: A prospective cohort study conducted in rural villages in the Capricorn District of Limpopo Province, South Africa. At birth, a cohort of 219 children was followed until they were one and three years of age. Data collected included the children’s anthropometric measurements, blood for biochemical analysis (full blood count, ferritin, folate and vitamin B12) and socio-demographic status.Results: At one year, anaemia (Hb < 11 g/dL) was present in 52% of the children, decreasing to 22% by the third year. Iron deficiency (ferritin < 12 µg/mL) was common in these children (39% and 33% at one year and three years, respectively) particularly in the presence of anaemia. Folate and vitamin B12 deficiencies (< 5 ng/mL and < 145 pg/mL, respectively) were common at one year, with the children accumulating enough vitamin B12 by three years; however, folate deficiency levels remained fairly constant between the two time points.Conclusion: There was a high prevalence of anaemia in the study participants at one year and three years of age. Factors that increased the risk of anaemia at three years were: a mother with only a primary school education, anaemia at one year, male gender, overweight, and combined overweight and stunting. Protective factors against anaemia were having a younger mother who served as the main caregiver.
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Abstract
About three-fourths of the total world population live in the tropics but consume only 6% of worldwide food production and contribute 15% of the world's net revenue explaining the short life expectancy, high infantile mortality, and poor daily caloric intake; moreover, lack of clean drinking water and deficient sanitation promote water-borne infections, diarrhea, and risk of malabsorption that contribute to the prevalence of malnutrition in the tropics. One-third of the world's population consumes insufficient iodine increasing the risk for mental retardation and deafness due to maternal hypothyroidism. The main nutritional syndromes comprise protein-energy malnutrition (marasmus and kwashiorkor); nutritional neuropathies, myelopathies and neuromyelopathies, as well as specific deficiencies of vitamins and micronutrients including iodine, iron, zinc, and selenium.
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Vitamin B-12 supplementation of rural Mexican women changes biochemical vitamin B-12 status indicators but does not affect hematology or a bone turnover marker. J Nutr 2012; 142:1881-7. [PMID: 22915298 DOI: 10.3945/jn.112.165712] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A high prevalence of low serum vitamin B-12 concentrations has been reported in studies and surveys in Latin America including Mexico, but the functional consequences are unknown. This randomized controlled trial assessed the response to a high-dose vitamin B-12 supplementation of women in rural Querétaro, Mexico. Participants aged 20-59 y were stratified at baseline to deficient, marginal, and adequate status groups (serum vitamin B-12, 75-148, 149-220, and >220 pmol/L, respectively), and each group was randomized to vitamin B-12 treatment (single dose of 1 mg i.m. then 500 μg/d orally for 3 mo, n = 70) or placebo (n = 62). Measures at baseline and 3 mo included: complete blood count, serum vitamin B-12, holotranscobalamin (holoTC), folate, ferritin, C-reactive protein (CRP), bone alkaline phosphatase, and methylmalonic acid (MMA) and plasma total homocysteine (tHcy). At baseline, 11% of the women were vitamin B-12 deficient and 22% had marginal status. HoloTC was low (<35 pmol/L) in 23% and correlated with serum vitamin B-12 (r = 0.7; P < 0.001). Elevated MMA (>271 nmol/L) and tHcy (>12 μmol/L) occurred in 21 and 31%, respectively, and correlated with serum vitamin B-12 (r = -0.28, P < 0.0007 and r = -0.20, P < 0.01, respectively). Supplementation increased serum vitamin B-12 and holoTC and lowered MMA and tHcy, normalizing all values except for elevated tHcy in 21% of the women. Supplementation did not affect hematology or bone-specific alkaline phosphatase. Vitamin B-12 supplementation normalized biochemical indicators of vitamin B-12 status in the treatment group but did not affect the functional outcomes measured.
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Relationship between vitamin B12, folate and homocysteine levels and H. pylori infection in patients with functional dyspepsia: a cross-section study. BMC Res Notes 2012; 5:206. [PMID: 22546014 PMCID: PMC3497610 DOI: 10.1186/1756-0500-5-206] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 04/30/2012] [Indexed: 12/30/2022] Open
Abstract
Background H. pylori infection has been associated with many micronutrient deficiencies. There is a dearth of data from communities with nutritional deficiencies and high prevalence of H. pylori infection. The aim of this study was to determine the impact of H. pylori infection on serum levels of vitamin B12, folate and homocysteine in patients with functional dyspepsia (FD). Methods One hundred and thirty-two patients with FD undergoing gastroscopy were enrolled. The serum was analyzed for B12, folate and homocysteine levels before gastroscopy. H. pylori infection was diagnosed by histopathological examination of gastric biopsies and urea breath test. An independent sample t-test and the Mann–Whitney test were used to compare mean serum concentrations of biomarkers between H. pylori-positive and H. pylori-negative groups of patients. A Chi-square test was performed to assess the differences among proportions, while Spearman’s rho was used for correlation analysis between levels of B12 and homocysteine. Results The mean age of the group was 40.3 ± 11.5 (19–72) years. Folate deficiency was seen in 43 (34.6%), B12 deficiency in 30 (23.1%) and hyperhomocysteinemia in 60 (46.2%) patients. H. pylori was present in 80 (61.5%) patients with FD while it was absent in 50 (38.5%). Mean serum levels of B12, folate and homocysteine in the H. pylori-positive group of patients were not significantly different from the levels in the H. pylori-negative group (357 ± 170 vs. 313 ± 136 pg/mL; p = 0.13), (4.35 ± 1.89 vs. 4.42 ± 1.93 ng/mL; p = 0.84); (15.88 ± 8.97 vs. 16.62 ± 7.82 μmol/L; p = 0.24); respectively. B12 deficiency (≤200 pg/mL) was 23.8% in the H. pylori-positive patients versus 22.0% in the H. pylori-negative patients. Folate deficiency (≤3.5 ng/mL) was 33.8% in the H. pylori-positive group versus 36% in the H. pylori-negative group. Hyperhomocysteinemia (>15 μmol/L) was present in 46.2% of H. pylori-positive patients compared to 44% in the H. pylori-negative group. Correlation analysis indicated that serum B12 levels were inversely associated with serum levels of homocysteine in patients with FD (rho = −0.192; p = 0.028). Conclusions This study demonstrated an inverse relationship between serum levels of B12 and homocysteine in patients with FD. Moreover, no impact of the presence of H. pylori was found on B12, folate and homocysteine levels in such patients.
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Vitamin B-12 status is associated with socioeconomic level and adherence to an animal food dietary pattern in Colombian school children. J Nutr 2008; 138:1391-8. [PMID: 18567766 DOI: 10.1093/jn/138.7.1391] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Vitamin B-12 is related to neurocognitive function in school-age children, yet sociodemographic and dietary correlates of vitamin B-12 status in this age group are not well characterized. The prevalences of vitamin B-12 or folate deficiencies in Colombia are unknown. We conducted a cross-sectional study in a representative sample of 2800 low- and middle-income children aged 5-12 y from Bogotá's public schools. Plasma vitamin B-12 and erythrocyte folate concentrations (mean +/- SD) were 327 +/- 106 pmol/L and 858 +/- 256 nmol/L, respectively. The prevalence of vitamin B-12 deficiency (<148 pmol/L) was 1.6% and the prevalence of marginal status (148-221 pmol/L) was 15.0%. Only 2 children had folate deficiency (<305 nmol/L). In multivariate analysis, mean vitamin B-12 concentrations significantly decreased with age and were 15 pmol/L higher in girls than boys (95%CI = 8, 23). Vitamin B-12 was inversely related to the mother's parity and positively associated with the amount of money spent on food per person per day at home and the household's neighborhood socioeconomic status (SES) classification. Folate concentrations were lower in girls than in boys and significantly increased with the household's SES. We identified 4 dietary patterns with principal components analysis of a FFQ in a random subsample (n = 972). Plasma vitamin B-12 was strongly, positively associated with a pattern that included frequent intake of beef, chicken, and dairy products in a dose-response manner (P-trend, adjusted, = 0.008). Low vitamin B-12 status is not negligible in Colombian school children and is associated with poverty and marginal intake of animal food sources.
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Abstract
This review describes current knowledge of the main causes of vitamin B12 and folate deficiency. The most common explanations for poor vitamin B12 status are a low dietary intake of the vitamin (i.e., a low intake of animal-source foods) and malabsorption. Although it has long been known that strict vegetarians (vegans) are at risk for vitamin B12 deficiency, evidence now indicates that low intakes of animal-source foods, such as occur in some lacto-ovo vegetarians and many less-industrialized countries, cause vitamin B12 depletion. Malabsorption of the vitamin is most commonly observed as food-bound cobalamin malabsorption due to gastric atrophy in the elderly, and probably as a result of Helicobacter pylori infection. There is growing evidence that gene polymorphisms in transcobalamins affect plasma vitamin B12 concentrations. The primary cause of folate deficiency is low intake of sources rich in the vitamin, such as legumes and green leafy vegetables, and the consumption of these foods may explain why folate status can be adequate in relatively poor populations. Other situations in which the risk of folate deficiency increases include lactation and alcoholism.
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Prevalent vitamin B-12 deficiency in twelve-month-old Guatemalan infants is predicted by maternal B-12 deficiency and infant diet. J Nutr 2007; 137:1307-13. [PMID: 17449597 DOI: 10.1093/jn/137.5.1307] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Approximately one-third of low-income women and children studied in Guatemala are reported to have deficient (<148 pmol/L) or marginal (148-220 pmol/L) plasma vitamin B-12 concentrations. Because vitamin B-12 deficiency can adversely affect infant development and cognitive function, the present study examined predictors of deficient plasma vitamin B-12 concentrations at the age of 12 mo. Analyses were performed on baseline data from a randomized clinical trial in 304 Guatemalan infants, 80% of whom were partially breast-fed, and their mothers. Exclusion criteria for infants included twins, severe stunting or moderate wasting, reported major health problems, severe developmental delay, hemoglobin <95 g/L, maternal age <17 y, and maternal pregnancy >3 mo. Data collected included socio-economic status, infant anthropometry, vitamin B-12 intake from complementary foods, and breast-feeding frequency reported by mothers. A complete blood count and plasma vitamin B-12, folate, ferritin, and C-reactive protein were measured. Deficient or marginal plasma vitamin B-12 concentrations were found in 49% of infants and 68% of mothers. The mean intake of maternal vitamin B-12 was 3.1 microg/d, and infants consumed 2.2 microg/d from complementary foods. In linear regression analysis, infant plasma B-12 concentration was strongly and positively associated with maternal plasma vitamin B-12 and B-12 intake from complementary foods (predominantly powdered cow's milk), and inversely associated with frequency of breast-feeding and larger household size (P < 0.0001). Vitamin B-12 supplementation of lactating women, food fortification, and education to improve infant's vitamin B-12 status are potential interventions that can improve the vitamin B-12 status of mothers and infants in this population.
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Serum ferritin, vitamin B(12), folate, and zinc levels in children infected with Helicobacter pylori. Dig Dis Sci 2007; 52:405-10. [PMID: 17211708 DOI: 10.1007/s10620-006-9422-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2005] [Accepted: 05/01/2006] [Indexed: 12/11/2022]
Abstract
We sought to explore the relationship between Helicobacter pylori infection and serum ferritin, vitamin B(12), folate, and zinc status among children. Fifty patients aged 5-18 years who underwent upper gastrointestinal endoscopy because of dyspeptic symptoms, were studied, prospectively. Patients were grouped as H. pylori positive (group 1, n=32) or H. pylori negative (group 2, n=18) by histopathologic examination and rapid urease test. Fasting serum ferritin, vitamin B(12), folate, and zinc levels of patients were measured. Both groups were indifferent according to age, gender, height standard deviation score (H(SDS)), and weight standard deviation score (W(SDS)). Serum ferritin levels were 33+/-26 and 50+/-46 ng/mL (P=.098), vitamin B(12) levels were 303+/-135 and 393+/-166 pg/mL (P=.042), folate levels were 9.64+/-3.2 and 9.61+/-2.8 ng/mL (P=.979), and zinc levels were 95+/-48 and 87+/-31 mug/dL (P=.538), in groups 1 and 2, respectively. Ferritin levels of 14 (43.8%) patients in group 1 and 6 (33.3%) patients in group 2 were below the normal range (P=.470). Serum vitamin B(12) levels of 9 children (28%) in group 1 and 2 children (11%) in group 2 were below the normal range (P=.287). The findings of the present study suggest that H. pylori infection has a negative effect on serum ferritin and vitamin B(12) levels in children. This negative effect on vitamin B(12) levels is rather marked in contrast to that on ferritin levels. H. pylori infection has no significant effect on serum folate or zinc levels among children.
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Abstract
There is growing interest in the potential for folic acid fortification in the Americas and recognition of the high prevalence of low plasma vitamin B12 concentrations reported in various studies. This review summarized available data on plasma vitamin B12 and folate concentrations in the Americas. At least 40% of individuals had deficient or marginal plasma vitamin B12 concentrations in almost all locations and across age groups. Low plasma folate concentrations were less common. It is hypothesized that vitamin B12 deficiency may result from a low intake of animal source foods, while a higher intake of refined flour may result in low plasma folate.
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