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Jacob Selhub - One of the best experts on this subject based on the ideXlab platform.
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folate <B>VitaminB> B 12 interaction in relation to cognitive impairment anemia and Biochemical indicators of <B>VitaminB> B 12 deficiency
The American Journal of Clinical Nutrition, 2009Co-Authors: Jacob Selhub, Martha Savaria Morris, Paul F Jacques, Irwin H RosenbergAbstract:Previous reports on pernicious anemia treatment suggested that high folic acid intake adversely influences the natural history of <B>VitaminB> B-12 deficiency, which affects many elderly individuals. However, experimental investigation of this hypothesis is unethical, and the few existing oBservational data are inconclusive. With the use of data from the 1999–2002 National Health and Nutrition Examination Survey (NHANES), we evaluated the interaction Between high serum folate and low <B>VitaminB> B-12 status [ie, plasma <B>VitaminB> B-12 210 nmol/L] with respect to anemia and cognitive impairment. With suBjects having Both plasma folate ≤ 59 nmol/L and normal <B>VitaminB> B-12 status as the referent category, odds ratios for the prevalence of anemia compared with normal hemogloBin concentration and impaired compared with unimpaired cognitive function were 2.1 (95% CI: 1.1, 3.7) and 1.7 (95% CI: 1.01, 2.9), respectively, for those with low <B>VitaminB> B-12 status But normal serum folate and 4.9 (95% CI: 2.3, 10.6) and 5.0 (95% CI: 2.7, 9.5), respectively, for those with low <B>VitaminB> B-12 status and plasma folate >59 nmol/L. Among suBjects with low <B>VitaminB> B-12 status, mean circulating <B>VitaminB> B-12 was 228 pmol/L for the normal-folate suBgroup and 354 pmol/L for the high-folate suBgroup. We suBsequently showed increases in circulating homocysteine and MMA concentrations with increasing serum folate among NHANES participants with serum <B>VitaminB> B-12 < 148 pmol/L, whereas the opposite trends occurred among suBjects with serum <B>VitaminB> B-12 ≥ 148 pmol/L. These interactions, which were not seen in NHANES III Before fortification, imply that, in <B>VitaminB> B-12 deficiency, high folate status is associated with impaired activity of the 2 <B>VitaminB> B-12–dependent enzymes, methionine synthase and MMA–coenzyme A mutase.
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folate <B>VitaminB> B 12 interaction in relation to cognitive impairment anemia and Biochemical indicators of <B>VitaminB> B 12 deficiency
The American Journal of Clinical Nutrition, 2009Co-Authors: Jacob Selhub, Martha Savaria Morris, Paul F Jacques, Irwin H RosenbergAbstract:Previous reports on pernicious anemia treatment suggested that high folic acid intake adversely influences the natural history of <B>VitaminB> B-12 deficiency, which affects many elderly individuals. However, experimental investigation of this hypothesis is unethical, and the few existing oBservational data are inconclusive. With the use of data from the 1999–2002 National Health and Nutrition Examination Survey (NHANES), we evaluated the interaction Between high serum folate and low <B>VitaminB> B-12 status [ie, plasma <B>VitaminB> B-12 210 nmol/L] with respect to anemia and cognitive impairment. With suBjects having Both plasma folate ≤ 59 nmol/L and normal <B>VitaminB> B-12 status as the referent category, odds ratios for the prevalence of anemia compared with normal hemogloBin concentration and impaired compared with unimpaired cognitive function were 2.1 (95% CI: 1.1, 3.7) and 1.7 (95% CI: 1.01, 2.9), respectively, for those with low <B>VitaminB> B-12 status But normal serum folate and 4.9 (95% CI: 2.3, 10.6) and 5.0 (95% CI: 2.7, 9.5), respectively, for those with low <B>VitaminB> B-12 status and plasma folate >59 nmol/L. Among suBjects with low <B>VitaminB> B-12 status, mean circulating <B>VitaminB> B-12 was 228 pmol/L for the normal-folate suBgroup and 354 pmol/L for the high-folate suBgroup. We suBsequently showed increases in circulating homocysteine and MMA concentrations with increasing serum folate among NHANES participants with serum <B>VitaminB> B-12 < 148 pmol/L, whereas the opposite trends occurred among suBjects with serum <B>VitaminB> B-12 ≥ 148 pmol/L. These interactions, which were not seen in NHANES III Before fortification, imply that, in <B>VitaminB> B-12 deficiency, high folate status is associated with impaired activity of the 2 <B>VitaminB> B-12–dependent enzymes, methionine synthase and MMA–coenzyme A mutase.
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plasma folate <B>VitaminB> B 6 <B>VitaminB> B 12 and risk of Breast cancer in women
The American Journal of Clinical Nutrition, 2008Co-Authors: Nancy R Cook, Jacob Selhub, Joann E Manson, Julie E Buring, Shumin M ZhangAbstract:BACKGROUND: B <B>VitaminB>s such as folate, <B>VitaminB> B-6, and <B>VitaminB> B-12 are coenzymes that are important for DNA integrity and staBility. Deficiency in these B <B>VitaminB>s may promote tumor carcinogenesis. OBJECTIVE: We prospectively evaluated plasma concentrations of folate, pyridoxal 5-phosphate (PLP; the principal active form of <B>VitaminB> B-6), and <B>VitaminB> B-12 in relation to Breast cancer risk. DESIGN: We included 848 incident cases of invasive Breast cancer identified as of 31 March 2004, and 848 individually matched control suBjects from 28 345 women in the Women's Health Study aged > or =45 y who provided Blood samples and had no history of cancer and cardiovascular disease at Baseline in 1993. Logistic regression controlling for matching factors and other risk factors for Breast cancer was used to estimate relative risks (RRs) and 95% CIs. All statistical tests were 2 sided. RESULTS: Plasma concentrations of folate, PLP, and <B>VitaminB> B-12 were not associated with overall risk of Breast cancer. Women in the highest quintile group relative to those in the lowest quintile had multivariate RRs of 1.42 (95% CI: 1.00, 2.02) for plasma folate (P for trend = 0.21), 0.91 (95% CI: 0.63, 1.30) for plasma PLP (P for trend = 0.48), and 1.29 (95% CI: 0.92, 1.82) for plasma <B>VitaminB> B-12 (P for trend = 0.18). However, higher plasma folate concentrations were moderately associated with an increased risk of developing premenopausal Breast cancer (P for trend = 0.04) and for developing estrogen receptor (ER)-positive or progesterone receptor (PR)-positive Breast tumors (P for trend < or = 0.06). Conversely, an inverse association was seen Between plasma PLP and postmenopausal Breast cancer (P for trend = 0.04). CONCLUSIONS: Data from this study suggest that B <B>VitaminB>s, including folate, <B>VitaminB> B-6, and <B>VitaminB> B-12, may confer little or no reduction in overall risk of developing Breast cancer. The oBserved positive associations of folate status with risk of developing premenopausal Breast cancer and ER-positive or PR-positive tumors are unexpected. Additional research is needed to elucidate the role of folate in Breast cancer development.
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Breakfast cereal fortified with folic acid <B>VitaminB> B 6 and <B>VitaminB> B 12 increases <B>VitaminB> concentrations and reduces homocysteine concentrations a randomized trial
The American Journal of Clinical Nutrition, 2004Co-Authors: Katherine L Tucker, Beth H Olson, Peter J Bakun, Gerard E Dallal, Jacob Selhub, Irwin H RosenbergAbstract:Background: High homocysteine and low B <B>VitaminB> concentrations have Been linked to the risk of vascular disease, stroke, and dementia and are relatively common in older adults. OBjective: We assessed the effect of Breakfast cereal fortified with folic acid, <B>VitaminB> B-6, and <B>VitaminB> B-12 on <B>VitaminB> and homocysteine status. Design: A randomized, douBle-Blind trial was conducted in 189 volunteers aged 50 – 85 y. The suBjects had no history of hypertension, anemia, asthma, cancer, or cardiovascular or digestive disease and did not regularly consume multiple or B <B>VitaminB> supplements or highly fortified Breakfast cereal. SuBjects were randomly assigned to consume 1 cup (0.24 L) Breakfast cereal fortified with 440 g folic acid, 1.8 mg <B>VitaminB> B-6, and 4.8g <B>VitaminB> B-12 or placeBo cereal for 12 wk. Blood was drawn at 0, 2, 12, and 14 wk. Methionineloading tests were conducted at Baseline and week 14. Results: Final Baseline-adjusted plasma homocysteine concentrations were significantly lower and B <B>VitaminB> concentrations were significantly higher in the treatment group than in the placeBo group (P 0.001). The percentage of suBjects with plasma folate concentrations 11 nmol/L decreased from 2% to 0%, with <B>VitaminB> B-12 concentrations 185 pmol/L from 9% to 3%, with <B>VitaminB> B-6 concentrations 20 nmol/L from 6% to 2%, and with homocysteine concentrations 10.4 mol/L (women) or 11.4 mol/L (men) from 6.4% to 1.6%. The percentage of control suBjects with values Beyond these cutoff points remained nearly constant or increased. Conclusions: In this relatively healthy group of volunteers, consumption of 1 cup fortified Breakfast cereal daily significantly increased B <B>VitaminB> and decreased homocysteine concentrations, including postmethionine-load homocysteine concentrations. Am J Clin Nutr 2004;79:805–11.
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plasma <B>VitaminB> B 12 concentrations relate to intake source in the framingham offspring study
The American Journal of Clinical Nutrition, 2000Co-Authors: Katherine L Tucker, Gerard E Dallal, Irwin H Rosenberg, Paul F Jacques, Sharron Rich, P W F Wilson, Jacob SelhubAbstract:Background: Low <B>VitaminB> B-12 status is prevalent among the elderly, But few studies have examined the association Between <B>VitaminB> B-12 status and intake. OBjective: We hypothesized that <B>VitaminB> B-12 concentrations vary according to intake source. Design: Plasma concentrations and dietary intakes were assessed cross-sectionally for 2999 suBjects in the Framingham Offspring Study. The prevalence of <B>VitaminB> B-12 concentrations 4 times/wk (12%) and those who consumed no fortified cereal (23%) and Between those in the highest and those in the lowest tertile of dairy intake (13% compared with 24%, respectively), But no significant differences By meat tertile. Regression of plasma <B>VitaminB> B-12 on log of intake, By source, yielded significant slopes for each contriButor adjusted for the others. For the total group, h = 40.6 for <B>VitaminB> B-12 from <B>VitaminB> supplements. Among non-supplement-users, B = 56.4 for dairy products, 35.2 for cereal, and 16.7 for meat. Only the meat slope differed significantly from the others. Conclusions: In contrast with previous reports, plasma <B>VitaminB> B-12 concentrations were associated with <B>VitaminB> B-12 intake. Use of supplements, fortified cereal, and milk appears to protect against lower concentrations. Further research is needed to investigate possiBle differences in BioavailaBility.
Lindsay H. Allen - One of the best experts on this subject based on the ideXlab platform.
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<B>VitaminB> B 12 concentrations in Breast milk are low and are not associated with reported household hunger recent animal source food or <B>VitaminB> B 12 intake in women in rural kenya
Journal of Nutrition, 2016Co-Authors: Anne M Williams, Lindsay H. Allen, Caroline J Chantry, Sera L Young, Beryl Achando, Benjamin F Arnold, John M Colford, Holly N Dentz, Daniela HampelAbstract:Author(s): Williams, AM; Chantry, CJ; Young, SL; Achando, BS; Allen, LH; Arnold, BF; Colford, JM; Dentz, HN; Hampel, D; Kiprotich, MC; Lin, A; Null, CA; NyamBane, GM; ShahaB-Ferdows, S; Stewart, CP | ABstract: © 2016 American Society for Nutrition. Background: Breast milk <B>VitaminB> B-12 concentration may Be inadequate in regions in which animal-source food consumption is low or infrequent. <B>VitaminB> B-12 deficiency causes megaloBlastic anemia and impairs growth and development in children. OBjective: We measured <B>VitaminB> B-12 in Breast milk and examined its associations with household hunger, recent animalsource food consumption, and <B>VitaminB> 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 <B>VitaminB> 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 <B>VitaminB> 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) <B>VitaminB> B-12 intake was 1.5 μg/d (0.3, 9.7 mg/d), and 60% of women consumed l 2.4 μg/d, the estimated average requirement during lactation. Median (IQR) Breast milk <B>VitaminB> B-12 concentration was 113 pmol/L (61, 199 pmol/L); 89% had concentrations l 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 <B>VitaminB> B-12 intake were not associated with Breast milk <B>VitaminB> B-12 concentrations. Maternal age was negatively associated with Breast milk <B>VitaminB> B-12 concentrations. Conclusion: Most lactating Kenyan women consumed less than the estimated average requirement of <B>VitaminB> B-12 and had low Breast milk <B>VitaminB> B-12 concentrations. We recommend interventions that improve <B>VitaminB> B-12 intake in lactating Kenyan women to foster maternal health and child development.
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<B>VitaminB> B 12 supplementation during pregnancy and early lactation increases maternal Breast milk and infant measures of <B>VitaminB> B 12 status
Journal of Nutrition, 2014Co-Authors: Christopher Duggan, Krishnamachari Srinivasan, Julia L Finkelstein, Tinku Thomas, Tinu Samuel, Ramya Rajendran, Sumithra Muthayya, Ammu Lukose, Wafaie W Fawzi, Lindsay H. AllenAbstract:Pregnant women in resource-poor areas are at risk of multiple micronutrient deficiencies, and indicators of low <B>VitaminB> B-12 status have Been associated with adverse pregnancy outcomes, including anemia, low Birth weight, and intrauterine growth retardation. To evaluate whether daily oral <B>VitaminB> B-12 supplementation during pregnancy increases maternal and infant measures of <B>VitaminB> B-12 status, we performed a randomized, placeBo-controlled clinical trial. Pregnant women <14 wk of gestation in Bangalore, India, were randomly assigned to receive daily oral supplementation with <B>VitaminB> B-12 (50 μg) or placeBo through 6 wk postpartum. All women were administered iron and folic acid supplements throughout pregnancy. One hundred eighty-three women were randomly assigned to receive <B>VitaminB> B-12 and 183 to receive placeBo. Compared with placeBo recipients, <B>VitaminB> B-12-supplemented women had significantly higher plasma <B>VitaminB> B-12 concentrations at Both the second (median <B>VitaminB> B-12 concentration: 216 vs. 111 pmol/L, P < 0.001) and third (median: 184 vs. 105 pmol/L, P < 0.001) trimesters. At 6 wk postpartum, median Breast milk <B>VitaminB> B-12 concentration was 136 pmol/L in <B>VitaminB> B-12-supplemented women vs. 87 pmol/L in the placeBo group (P < 0.0005). Among <B>VitaminB> B-12-supplemented women, the incidence of delivering an infant with intrauterine growth retardation was 33 of 131 (25%) vs. 43 of 125 (34%) in those administered placeBo (P = 0.11). In a suBset of infants tested at 6 wk of age, median plasma <B>VitaminB> B-12 concentration was 199 pmol/L in those Born to supplemented women vs. 139 pmol/L in the placeBo group (P = 0.01). Infant plasma methylmalonic acid and homocysteine concentrations were significantly lower in the <B>VitaminB> B-12 group as well. Oral supplementation of urBan Indian women with <B>VitaminB> B-12 throughout pregnancy and early lactation significantly increases <B>VitaminB> B-12 status of mothers and infants. It is important to determine whether there are correlations Between these findings and neurologic and metaBolic functions. This trial was registered at clinicaltrials.gov as NCT00641862.
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<B>VitaminB> B 12 supplementation during pregnancy and early lactation increases maternal Breast milk and infant measures of <B>VitaminB> B 12 status
Journal of Nutrition, 2014Co-Authors: Christopher Duggan, Krishnamachari Srinivasan, Julia L Finkelstein, Tinku Thomas, Ramya Rajendran, Sumithra Muthayya, Ammu Lukose, Wafaie W Fawzi, Tinu Mary Samuel, Lindsay H. AllenAbstract:Pregnant women in resource-poor areas are at risk of multiple micronutrient deficiencies, and indicators of low <B>VitaminB> B-12 status have Been associated with adverse pregnancy outcomes, including anemia, low Birth weight, and intrauterine growth retardation. To evaluate whether daily oral <B>VitaminB> B-12 supplementation during pregnancy increases maternal and infant measures of <B>VitaminB> B-12 status, we performed a randomized, placeBo-controlled clinical trial. Pregnant women <14 wk of gestation in Bangalore, India, were randomly assigned to receive daily oral supplementation with <B>VitaminB> B-12 (50 μg) or placeBo through 6 wk postpartum. All women were administered iron and folic acid supplements throughout pregnancy. One hundred eighty-three women were randomly assigned to receive <B>VitaminB> B-12 and 183 to receive placeBo. Compared with placeBo recipients, <B>VitaminB> B-12–supplemented women had significantly higher plasma <B>VitaminB> B-12 concentrations at Both the second (median <B>VitaminB> B-12 concentration: 216 vs. 111 pmol/L, P < 0.001) and third (median: 184 vs. 105 pmol/L, P < 0.001) trimesters. At 6 wk postpartum, median Breast milk <B>VitaminB> B-12 concentration was 136 pmol/L in <B>VitaminB> B-12–supplemented women vs. 87 pmol/L in the placeBo group (P < 0.0005). Among <B>VitaminB> B-12–supplemented women, the incidence of delivering an infant with intrauterine growth retardation was 33 of 131 (25%) vs. 43 of 125 (34%) in those administered placeBo (P = 0.11). In a suBset of infants tested at 6 wk of age, median plasma <B>VitaminB> B-12 concentration was 199 pmol/L in those Born to supplemented women vs. 139 pmol/L in the placeBo group (P = 0.01). Infant plasma methylmalonic acid and homocysteine concentrations were significantly lower in the <B>VitaminB> B-12 group as well. Oral supplementation of urBan Indian women with <B>VitaminB> B-12 throughout pregnancy and early lactation significantly increases <B>VitaminB> B-12 status of mothers and infants. It is important to determine whether there are correlations Between these findings and neurologic and metaBolic functions. This trial was registered at clinicaltrials.gov as {"type":"clinical-trial","attrs":{"text":"NCT00641862","term_id":"NCT00641862"}}NCT00641862.
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<B>VitaminB> B 12 supplementation of rural mexican women changes Biochemical <B>VitaminB> B 12 status indicators But does not affect hematology or a Bone turnover marker
Journal of Nutrition, 2012Co-Authors: Setareh Shahabferdows, Miriam Aracely Anayaloyola, Hayde Vergaracastaneda, Jorge L Rosado, William R Keyes, John W Newman, Joshua W Miller, Lindsay H. AllenAbstract:A high prevalence of low serum <B>VitaminB> 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 <B>VitaminB> B-12 supplementation of women in rural Queretaro, Mexico. Participants aged 20-59 y were stratified at Baseline to deficient, marginal, and adequate status groups (serum <B>VitaminB> B-12, 75-148, 149-220, and >220 pmol/L, respectively), and each group was randomized to <B>VitaminB> 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 <B>VitaminB> 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 <B>VitaminB> B-12 deficient and 22% had marginal status. HoloTC was low ( 271 nmol/L) and tHcy (>12 μmol/L) occurred in 21 and 31%, respectively, and correlated with serum <B>VitaminB> B-12 (r = -0.28, P < 0.0007 and r = -0.20, P < 0.01, respectively). Supplementation increased serum <B>VitaminB> 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. <B>VitaminB> B-12 supplementation normalized Biochemical indicators of <B>VitaminB> B-12 status in the treatment group But did not affect the functional outcomes measured.
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how common is <B>VitaminB> B 12 deficiency
The American Journal of Clinical Nutrition, 2009Co-Authors: Lindsay H. AllenAbstract:In considering the <B>VitaminB> B-12 fortification of flour, it is important to know who is at risk of <B>VitaminB> B-12 deficiency and whether those individuals would Benefit from flour fortification. This article reviews current knowledge of the prevalence and causes of <B>VitaminB> B-12 deficiency and considers whether fortification would improve the status of deficient suBgroups of the population. In large surveys in the United States and the United Kingdom, approximately 6% of those aged > or =60 y are <B>VitaminB> B-12 deficient (plasma <B>VitaminB> B-12 < 148 pmol/L), with the prevalence of deficiency increasing with age. Closer to 20% have marginal status (plasma <B>VitaminB> B-12: 148-221 pmol/L) in later life. In developing countries, deficiency is much more common, starting in early life and persisting across the life span. Inadequate intake, due to low consumption of animal-source foods, is the main cause of low serum <B>VitaminB> B-12 in younger adults and likely the main cause in poor populations worldwide; in most studies, serum <B>VitaminB> B-12 concentration is correlated with intake of this <B>VitaminB>. In older persons, food-Bound coBalamin malaBsorption Becomes the predominant cause of deficiency, at least in part due to gastric atrophy, But it is likely that most elderly can aBsorB the <B>VitaminB> from fortified food. Fortification of flour with <B>VitaminB> B-12 is likely to improve the status of most persons with low stores of this <B>VitaminB>. However, intervention studies are still needed to assess efficacy and functional Benefits of increasing intake of the amounts likely to Be consumed in flour, including in elderly persons with varying degrees of gastric atrophy.
Helga Refsum - One of the best experts on this subject based on the ideXlab platform.
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<B>VitaminB> B 12 folic acid and growth in 6 to 30 month old children a randomized controlled trial
Pediatrics, 2015Co-Authors: Helga Refsum, Tor A Strand, Sunita Taneja, Tivendra Kumar, Mari S Manger, Chittaranjan S Yajnik, Nita BhandariAbstract:BACKGROUND: Folate and <B>VitaminB> B-12 are important for growth. Many children in low- and middle-income countries have inadequate intakes of these nutrients. METHODS: We undertook a randomized, placeBo controlled douBle-Blind trial in 1000 North Indian children, 6 to 35 months of age, providing twice the recommended daily allowance of folic acid and/or <B>VitaminB> B-12, or placeBo, daily for 6 months. By using a factorial design, we allocated children in a 1:1:1:1 ratio in Blocks of 16. We measured the effect of giving <B>VitaminB> B-12, folic acid, or the comBination of Both on linear and ponderal growth. We also identified predictors for growth in multiple linear regression models and effect modifiers for the effect of folic acid or <B>VitaminB> B-12 supplementation on growth. RESULTS: The overall effect of either of the <B>VitaminB>s was significant only for weight; children who received <B>VitaminB> B-12 increased their mean weight-for-age z scores By 0.07 (95% confidence interval: 0.01 to 0.13). Weight-for-age z scores and height-for-age z scores increased significantly after <B>VitaminB> B-12 supplementation in wasted, underweight, and stunted children. These suBgrouping variaBles significantly modified the effect of <B>VitaminB> B-12 on growth. <B>VitaminB> B-12 status at Baseline predicted linear and ponderal growth in children not receiving <B>VitaminB> B-12 supplements But not in those who did ( P -interaction CONCLUSIONS: We provide evidence that poor <B>VitaminB> B-12 status contriButes to poor growth. We recommend studies with larger doses and longer follow-up to confirm our findings.
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dietary sources of <B>VitaminB> B 12 and their association with plasma <B>VitaminB> B 12 concentrations in the general population the hordaland homocysteine study
The American Journal of Clinical Nutrition, 2009Co-Authors: Anna Vogiatzoglou, A D Smith, Eha Nurk, Paula Berstad, Christian A Drevon, P M Ueland, Stein Emil Vollset, Grethe S Tell, Helga RefsumAbstract:BACKGROUND: Limited information is availaBle on the association Between <B>VitaminB> B-12 status and intake from different dietary sources. OBJECTIVE: We investigated the relation of dietary intake of different food items with plasma <B>VitaminB> B-12 concentrations in the general population. DESIGN: A cross-sectional, population-Based study of 5937 suBjects in 2 age groups (47-49 and 71-74 y) from the Hordaland Homocysteine Study in Norway was conducted By using a food-frequency questionnaire and measurements of plasma <B>VitaminB> B-12 concentrations. RESULTS: A significant difference in plasma <B>VitaminB> B-12 concentrations was oBserved with increasing total <B>VitaminB> B-12 intake. A plateau was reached at an intake of approximately 10 microg/d. Plasma <B>VitaminB> B-12 was associated with intakes of increasing amounts of <B>VitaminB> B-12 from dairy products or fish (P for trend 0.27 micromol/L) in the total group and in 71-74-y-old suBjects. CONCLUSIONS: Dietary intake of dairy products and fish are significant contriButors to plasma <B>VitaminB> B-12 and may improve plasma <B>VitaminB> B-12 status. <B>VitaminB> B-12 appears to Be more BioavailaBle from dairy products; guidelines for improving <B>VitaminB> B-12 status should take this into consideration.
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<B>VitaminB> B 12 and cognition in the elderly
The American Journal of Clinical Nutrition, 2009Co-Authors: David A Smith, Helga RefsumAbstract:<B>VitaminB> B-12 deficiency is often associated with cognitive deficits. Here we review evidence that cognition in the elderly may also Be adversely affected at concentrations of <B>VitaminB> B-12 aBove the traditional cutoffs for deficiency. By using markers such as holotranscoBalamin and methylmalonic acid, it has Been found that cognition is associated with <B>VitaminB> B-12 status across the normal range. PossiBle mediators of this relation include Brain atrophy and white matter damage, Both of which are associated with low <B>VitaminB> B-12 status. Intervention trials have not Been adequately designed to test whether these associations are causal. Pending the outcome of Better trials, it is suggested that the elderly in particular should Be encouraged to maintain a good, rather than just an adequate, <B>VitaminB> B-12 status By dietary means.
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screening for <B>VitaminB> B 12 and folate deficiency in older persons
The American Journal of Clinical Nutrition, 2003Co-Authors: Robert Clarke, Helga Refsum, Jacqueline Birks, John Grimley Evans, Carole Johnston, Paul Sherliker, Per Magne Ueland, J Schneede, Joseph Mcpartlin, Ebba NexoAbstract:Background: <B>VitaminB> B-12 deficiency is usually accompanied By elevated concentrations of serum total homocysteine (tHcy) and methylmalonic acid (MMA). Folate deficiency also results in elevated tHcy. Measurement of these metaBolites can Be used to screen for functional <B>VitaminB> B-12 or folate deficiency. OBjective: We assessed the prevalence of <B>VitaminB> B-12 and folate deficiency in a population-Based study (n = 1562) of older persons living in Oxford City, United Kingdom. Design: We postulated that, as <B>VitaminB> B-12 or folate concentrations declined from adequate to impaired levels, tHcy (or MMA) concentrations would increase. Individuals were classified as Being at high risk of <B>VitaminB> B-12 deficiency if they had low <B>VitaminB> B-12 ( 0.35 � mol/L) or tHcy (> 15.0 � mol/L). Individuals were classified as Being at high risk of folate deficiency if they had low folate ( 15 � mol/L). Results: Cutoffs of 15.0 � mol/L for tHcy and 0.35 � mol/L for MMA identified persons with normal or elevated concentrations. Among persons aged 65‐74 and ≥ 75 y, respectively, � 10% and 20% were at high risk of <B>VitaminB> B-12 deficiency. ABout 10% and 20%, respectively, were also at high risk of folate deficiency. ABout 10% of persons with <B>VitaminB> B-12 deficiency also had folate deficiency. Conclusion: Use of tHcy or MMA among older persons with Borderline <B>VitaminB> concentrations may identify those at high risk of <B>VitaminB> B-12 deficiency who should Be considered for treatment. Am J Clin Nutr 2003;77:1241‐7.
Irwin H Rosenberg - One of the best experts on this subject based on the ideXlab platform.
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folate <B>VitaminB> B 12 interaction in relation to cognitive impairment anemia and Biochemical indicators of <B>VitaminB> B 12 deficiency
The American Journal of Clinical Nutrition, 2009Co-Authors: Jacob Selhub, Martha Savaria Morris, Paul F Jacques, Irwin H RosenbergAbstract:Previous reports on pernicious anemia treatment suggested that high folic acid intake adversely influences the natural history of <B>VitaminB> B-12 deficiency, which affects many elderly individuals. However, experimental investigation of this hypothesis is unethical, and the few existing oBservational data are inconclusive. With the use of data from the 1999–2002 National Health and Nutrition Examination Survey (NHANES), we evaluated the interaction Between high serum folate and low <B>VitaminB> B-12 status [ie, plasma <B>VitaminB> B-12 210 nmol/L] with respect to anemia and cognitive impairment. With suBjects having Both plasma folate ≤ 59 nmol/L and normal <B>VitaminB> B-12 status as the referent category, odds ratios for the prevalence of anemia compared with normal hemogloBin concentration and impaired compared with unimpaired cognitive function were 2.1 (95% CI: 1.1, 3.7) and 1.7 (95% CI: 1.01, 2.9), respectively, for those with low <B>VitaminB> B-12 status But normal serum folate and 4.9 (95% CI: 2.3, 10.6) and 5.0 (95% CI: 2.7, 9.5), respectively, for those with low <B>VitaminB> B-12 status and plasma folate >59 nmol/L. Among suBjects with low <B>VitaminB> B-12 status, mean circulating <B>VitaminB> B-12 was 228 pmol/L for the normal-folate suBgroup and 354 pmol/L for the high-folate suBgroup. We suBsequently showed increases in circulating homocysteine and MMA concentrations with increasing serum folate among NHANES participants with serum <B>VitaminB> B-12 < 148 pmol/L, whereas the opposite trends occurred among suBjects with serum <B>VitaminB> B-12 ≥ 148 pmol/L. These interactions, which were not seen in NHANES III Before fortification, imply that, in <B>VitaminB> B-12 deficiency, high folate status is associated with impaired activity of the 2 <B>VitaminB> B-12–dependent enzymes, methionine synthase and MMA–coenzyme A mutase.
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folate <B>VitaminB> B 12 interaction in relation to cognitive impairment anemia and Biochemical indicators of <B>VitaminB> B 12 deficiency
The American Journal of Clinical Nutrition, 2009Co-Authors: Jacob Selhub, Martha Savaria Morris, Paul F Jacques, Irwin H RosenbergAbstract:Previous reports on pernicious anemia treatment suggested that high folic acid intake adversely influences the natural history of <B>VitaminB> B-12 deficiency, which affects many elderly individuals. However, experimental investigation of this hypothesis is unethical, and the few existing oBservational data are inconclusive. With the use of data from the 1999–2002 National Health and Nutrition Examination Survey (NHANES), we evaluated the interaction Between high serum folate and low <B>VitaminB> B-12 status [ie, plasma <B>VitaminB> B-12 210 nmol/L] with respect to anemia and cognitive impairment. With suBjects having Both plasma folate ≤ 59 nmol/L and normal <B>VitaminB> B-12 status as the referent category, odds ratios for the prevalence of anemia compared with normal hemogloBin concentration and impaired compared with unimpaired cognitive function were 2.1 (95% CI: 1.1, 3.7) and 1.7 (95% CI: 1.01, 2.9), respectively, for those with low <B>VitaminB> B-12 status But normal serum folate and 4.9 (95% CI: 2.3, 10.6) and 5.0 (95% CI: 2.7, 9.5), respectively, for those with low <B>VitaminB> B-12 status and plasma folate >59 nmol/L. Among suBjects with low <B>VitaminB> B-12 status, mean circulating <B>VitaminB> B-12 was 228 pmol/L for the normal-folate suBgroup and 354 pmol/L for the high-folate suBgroup. We suBsequently showed increases in circulating homocysteine and MMA concentrations with increasing serum folate among NHANES participants with serum <B>VitaminB> B-12 < 148 pmol/L, whereas the opposite trends occurred among suBjects with serum <B>VitaminB> B-12 ≥ 148 pmol/L. These interactions, which were not seen in NHANES III Before fortification, imply that, in <B>VitaminB> B-12 deficiency, high folate status is associated with impaired activity of the 2 <B>VitaminB> B-12–dependent enzymes, methionine synthase and MMA–coenzyme A mutase.
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Breakfast cereal fortified with folic acid <B>VitaminB> B 6 and <B>VitaminB> B 12 increases <B>VitaminB> concentrations and reduces homocysteine concentrations a randomized trial
The American Journal of Clinical Nutrition, 2004Co-Authors: Katherine L Tucker, Beth H Olson, Peter J Bakun, Gerard E Dallal, Jacob Selhub, Irwin H RosenbergAbstract:Background: High homocysteine and low B <B>VitaminB> concentrations have Been linked to the risk of vascular disease, stroke, and dementia and are relatively common in older adults. OBjective: We assessed the effect of Breakfast cereal fortified with folic acid, <B>VitaminB> B-6, and <B>VitaminB> B-12 on <B>VitaminB> and homocysteine status. Design: A randomized, douBle-Blind trial was conducted in 189 volunteers aged 50 – 85 y. The suBjects had no history of hypertension, anemia, asthma, cancer, or cardiovascular or digestive disease and did not regularly consume multiple or B <B>VitaminB> supplements or highly fortified Breakfast cereal. SuBjects were randomly assigned to consume 1 cup (0.24 L) Breakfast cereal fortified with 440 g folic acid, 1.8 mg <B>VitaminB> B-6, and 4.8g <B>VitaminB> B-12 or placeBo cereal for 12 wk. Blood was drawn at 0, 2, 12, and 14 wk. Methionineloading tests were conducted at Baseline and week 14. Results: Final Baseline-adjusted plasma homocysteine concentrations were significantly lower and B <B>VitaminB> concentrations were significantly higher in the treatment group than in the placeBo group (P 0.001). The percentage of suBjects with plasma folate concentrations 11 nmol/L decreased from 2% to 0%, with <B>VitaminB> B-12 concentrations 185 pmol/L from 9% to 3%, with <B>VitaminB> B-6 concentrations 20 nmol/L from 6% to 2%, and with homocysteine concentrations 10.4 mol/L (women) or 11.4 mol/L (men) from 6.4% to 1.6%. The percentage of control suBjects with values Beyond these cutoff points remained nearly constant or increased. Conclusions: In this relatively healthy group of volunteers, consumption of 1 cup fortified Breakfast cereal daily significantly increased B <B>VitaminB> and decreased homocysteine concentrations, including postmethionine-load homocysteine concentrations. Am J Clin Nutr 2004;79:805–11.
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plasma <B>VitaminB> B 12 concentrations relate to intake source in the framingham offspring study
The American Journal of Clinical Nutrition, 2000Co-Authors: Katherine L Tucker, Gerard E Dallal, Irwin H Rosenberg, Paul F Jacques, Sharron Rich, P W F Wilson, Jacob SelhubAbstract:Background: Low <B>VitaminB> B-12 status is prevalent among the elderly, But few studies have examined the association Between <B>VitaminB> B-12 status and intake. OBjective: We hypothesized that <B>VitaminB> B-12 concentrations vary according to intake source. Design: Plasma concentrations and dietary intakes were assessed cross-sectionally for 2999 suBjects in the Framingham Offspring Study. The prevalence of <B>VitaminB> B-12 concentrations 4 times/wk (12%) and those who consumed no fortified cereal (23%) and Between those in the highest and those in the lowest tertile of dairy intake (13% compared with 24%, respectively), But no significant differences By meat tertile. Regression of plasma <B>VitaminB> B-12 on log of intake, By source, yielded significant slopes for each contriButor adjusted for the others. For the total group, h = 40.6 for <B>VitaminB> B-12 from <B>VitaminB> supplements. Among non-supplement-users, B = 56.4 for dairy products, 35.2 for cereal, and 16.7 for meat. Only the meat slope differed significantly from the others. Conclusions: In contrast with previous reports, plasma <B>VitaminB> B-12 concentrations were associated with <B>VitaminB> B-12 intake. Use of supplements, fortified cereal, and milk appears to protect against lower concentrations. Further research is needed to investigate possiBle differences in BioavailaBility.
Robert Clarke - One of the best experts on this subject based on the ideXlab platform.
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low <B>VitaminB> B 12 status and risk of cognitive decline in older adults
The American Journal of Clinical Nutrition, 2007Co-Authors: Robert Clarke, Jacqueline Birks, Per Magne Ueland, J Schneede, Ebba Nexo, John D Scott, Anne M Molloy, John EvansAbstract:Background:Elevatedtotalhomocysteine(tHcy)concentrationshave Beenassociatedwithcognitiveimpairment,Butitisunclearwhetherlow <B>VitaminB> B-12 or folate status is responsiBle for cognitive decline. OBjective: We examined the associations of cognitive decline with <B>VitaminB> B-12 and folate status in a longitudinal cohort study performed from 1993 to 2003 in Oxford, United Kingdom. Design: Cognitive function was assessed with the Mini-Mental StateExaminationon3occasionsduring10yandrelatedtoserum concentrations of <B>VitaminB> B-12, holotranscoBalamin (holoTC), tHcy, methylmalonic acid (MMA), and folate with the use of linear mixed models in 1648 participants who provided Blood in 1995. Results: Cognitive function declined aBruptly at younger ages in someparticipantsButremainedintactinothersuntilveryoldage.In multivariateregressionanalysesafteradjustmentforestaBlishedrisk factors,concentrationsofholoTC(amarkerofreduced<B>VitaminB>B-12 status), tHcy, and MMA predicted cognitive decline, But folate did not. A douBling in holoTC concentrations (from 50 to 100 pmol/L) was associated with a 30% slower rate of cognitive decline (0.137 to 0.083), whereas a douBling in tHcy (from 10 to 20 mol/L) or MMA (from 0.25 to 0.50mol/L) was associated with50% more rapid cognitive decline (0.090 to 0.169) and (0.104 to 0.169), respectively. After adjustment for all <B>VitaminB> markers simultaneously,theassociationsofcognitivedeclinewithholoTCand MMA remained significant. Conclusions: Low <B>VitaminB> B-12 status was associated with more rapidcognitivedecline.Randomizedtrialsarerequiredtodetermine the relevance of <B>VitaminB> B-12 supplementation for prevention of dementia. Am J Clin Nutr 2007;86:1384–91.
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effect of oral <B>VitaminB> B 12 with or without folic acid on cognitive function in older people with mild <B>VitaminB> B 12 deficiency a randomized placeBo controlled trial
The American Journal of Clinical Nutrition, 2006Co-Authors: Simone J P M Eussen, Robert Clarke, Per Magne Ueland, J Schneede, Lisette C P G M De Groot, Liesbeth W Joosten, Rubia J Bloo, Henk J Blom, W H L Hoefnagels, Wija A Van StaverenAbstract:BACKGROUND: <B>VitaminB> B-12 deficiency is associated with cognitive impairment in older people. However, evidence from randomized trials of the effects of <B>VitaminB> B-12 supplementation on cognitive function is limited and inconclusive. OBJECTIVE: The oBjective was to investigate whether daily supplementation with high doses of oral <B>VitaminB> B-12 alone or in comBination with folic acid has any Beneficial effects on cognitive function in persons aged >/=70 y with mild <B>VitaminB> B-12 deficiency. DESIGN: In a douBle-Blind, placeBo-controlled trial, 195 suBjects were randomly assigned to receive 1000 microg <B>VitaminB> B-12, 1000 microg <B>VitaminB> B-12 + 400 microg folic acid, or placeBo for 24 wk. <B>VitaminB> B-12 status was assessed on the Basis of methylmalonic acid, total homocysteine (tHcy), and holotranscoBalamin (holoTC) concentrations Before and after 12 and 24 wk of treatment. Cognitive function was assessed Before and after 24 wk of treatment with the use of an extensive neuropsychologic test Battery that included the domains of attention, construction, sensomotor speed, memory, and executive function. RESULTS: <B>VitaminB> B-12 status did not change significantly after treatment in the placeBo group; however, oral <B>VitaminB> B-12 supplementation corrected mild <B>VitaminB> B-12 deficiency. <B>VitaminB> B-12 + folic acid supplementation increased red Blood cell folate concentrations and decreased tHcy concentrations By 36%. Improvement in memory function was greater in the placeBo group than in the group who received <B>VitaminB> B-12 alone (P = 0.0036). Neither supplementation with <B>VitaminB> B-12 alone nor that in comBination with folic acid was accompanied By any improvement in other cognitive domains. CONCLUSION: Oral supplementation with <B>VitaminB> B-12 alone or in comBination with folic acid for 24 wk does not improve cognitive function.
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effect of oral <B>VitaminB> B 12 with or without folic acid on cognitive function in older people with mild <B>VitaminB> B 12 deficiency a randomized placeBo controlled trial
The American Journal of Clinical Nutrition, 2006Co-Authors: Simone J P M Eussen, Robert Clarke, Per Magne Ueland, J Schneede, Lisette C P G M De Groot, Liesbeth W Joosten, Rubia J Bloo, Henk J Blom, W H L Hoefnagels, Wija A Van StaverenAbstract:Effect of oral <B>VitaminB> B-12 with or without folic acid on cognitive function in older people with mild <B>VitaminB> B-12 deficiency : a randomized, placeBo-controlled trial.
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screening for <B>VitaminB> B 12 and folate deficiency in older persons
The American Journal of Clinical Nutrition, 2003Co-Authors: Robert Clarke, Helga Refsum, Jacqueline Birks, John Grimley Evans, Carole Johnston, Paul Sherliker, Per Magne Ueland, J Schneede, Joseph Mcpartlin, Ebba NexoAbstract:Background: <B>VitaminB> B-12 deficiency is usually accompanied By elevated concentrations of serum total homocysteine (tHcy) and methylmalonic acid (MMA). Folate deficiency also results in elevated tHcy. Measurement of these metaBolites can Be used to screen for functional <B>VitaminB> B-12 or folate deficiency. OBjective: We assessed the prevalence of <B>VitaminB> B-12 and folate deficiency in a population-Based study (n = 1562) of older persons living in Oxford City, United Kingdom. Design: We postulated that, as <B>VitaminB> B-12 or folate concentrations declined from adequate to impaired levels, tHcy (or MMA) concentrations would increase. Individuals were classified as Being at high risk of <B>VitaminB> B-12 deficiency if they had low <B>VitaminB> B-12 ( 0.35 � mol/L) or tHcy (> 15.0 � mol/L). Individuals were classified as Being at high risk of folate deficiency if they had low folate ( 15 � mol/L). Results: Cutoffs of 15.0 � mol/L for tHcy and 0.35 � mol/L for MMA identified persons with normal or elevated concentrations. Among persons aged 65‐74 and ≥ 75 y, respectively, � 10% and 20% were at high risk of <B>VitaminB> B-12 deficiency. ABout 10% and 20%, respectively, were also at high risk of folate deficiency. ABout 10% of persons with <B>VitaminB> B-12 deficiency also had folate deficiency. Conclusion: Use of tHcy or MMA among older persons with Borderline <B>VitaminB> concentrations may identify those at high risk of <B>VitaminB> B-12 deficiency who should Be considered for treatment. Am J Clin Nutr 2003;77:1241‐7.
