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Rawlings NG, Valenzuela AA, Allen LH, Heathcote JG. Isolated eyelid edema in Melkersson-Rosenthal syndrome: a case series. Eye (Lond) 2011; 26:163-6. [PMID: 22056858 DOI: 10.1038/eye.2011.285] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To report the clinicopathologic features of a series of patients with Melkersson-Rosenthal syndrome (MRS). METHODS Patients in this clinicopathological case series were identified through retrospective review. Five Caucasian patients (2 women and 3 men; age range, 46 to 73 years) with isolated eyelid swelling presented over an 11-month period to two Canadian tertiary Oculoplastic referral centres. All underwent clinical examination and had tissue biopsies. RESULTS The patients presented with non-pitting, non-pruritic, painless and recurrent eyelid swelling. None had evidence of cranial nerve palsy or fissured tongue. The duration of symptoms before referral was between 1-5 years. Histopathological examination showed granulomatous inflammation in four patients. Granulomatous folliculitis was a novel finding in three patients. CONCLUSIONS Monosymptomatic patients with MRS require a high index of suspicion. Histopathological confirmation is vital for the diagnosis.
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Ramakrishnan U, Goldenberg T, Allen LH. Do multiple micronutrient interventions improve child health, growth, and development? J Nutr 2011; 141:2066-75. [PMID: 21956959 DOI: 10.3945/jn.111.146845] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Micronutrient deficiencies are common and often co-occur in many developing countries. Several studies have examined the benefits of providing multiple micronutrient (MMN) interventions during pregnancy and childhood, but the implications for programs remain unclear. The key objective of this review is to summarize what is known about the efficacy of MMN interventions during early childhood on functional outcomes, namely, child health, survival, growth, and development, to guide policy and identify gaps for future research. We identified review articles including meta-analyses and intervention studies that evaluated the benefits of MMN interventions (3 or more micronutrients) in children (<5 y of age) using Pubmed and EMBASE. Several controlled trials (n = 45) and meta-analyses (n = 6) have evaluated the effects of MMN interventions primarily for child morbidity, anemia, and growth. Two studies found no effects on child mortality. The findings for respiratory illness and diarrhea are mixed, although suggestive of benefit when provided as fortified foods. There is evidence from several controlled trials (>25) and 2 meta-analyses that MMN interventions improve hemoglobin concentrations and reduce anemia, but the effects were small compared to providing only iron or iron with folic acid. Two recent meta-analyses and several intervention trials also indicated that MMN interventions improve linear growth compared to providing a placebo or single nutrients. Much less is known about the effects on MMN interventions during early childhood on motor and mental development. In summary, MMN interventions may result in improved outcomes for children in settings where micronutrient deficiencies are widespread.
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Dror DK, Allen LH. The Importance of Milk and other Animal-Source Foods for Children in Low-Income Countries. Food Nutr Bull 2011; 32:227-43. [DOI: 10.1177/156482651103200307] [Citation(s) in RCA: 167] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background Milk and other animal-source foods are concentrated dietary sources of macro- and micronutrients. Despite a global increase in milk production and consumption over the past decades, milk and other animal-source foods are often lacking in the diets of children in developing countries. Objective To evaluate the importance of milk and other animal-source food intake in promoting the growth, development, and health of children in low-income countries. Methods Original research articles describing observational and intervention studies with unfortified milk, fortified milk, and other animal-source foods in children were identified by searching the PubMed database. Results Consumption of milk and other animal-source foods by undernourished children improves anthropometric indices and cognitive function and reduces the prevalence of biochemical and functional nutritional deficiencies, reducing morbidity and mortality. Unfortified and fortified milk used in supplementation trials has been well tolerated and widely accepted by parents and children. Conclusions To improve the dietary quality of children in low-income countries and further the effort to eradicate extreme poverty and hunger in accordance with the United Nations Millennium Development Goals, additional research is necessary to identify and implement programs and policy supporting increased intake of milk and other animal-source foods.
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Pedersen TL, Keyes WR, Shahab-Ferdows S, Allen LH, Newman JW. Methylmalonic acid quantification in low serum volumes by UPLC–MS/MS. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:1502-6. [DOI: 10.1016/j.jchromb.2011.03.039] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 03/16/2011] [Accepted: 03/18/2011] [Indexed: 01/14/2023]
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Allen LH, Dror DK. Effects of animal source foods, with emphasis on milk, in the diet of children in low-income countries. NESTLE NUTRITION WORKSHOP SERIES. PAEDIATRIC PROGRAMME 2011; 67:113-30. [PMID: 21335994 DOI: 10.1159/000325579] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
This review evaluates evidence for benefits of including animal source foods (ASF) in the diets of children in developing countries. In observational studies, a higher usual intake of ASF in such countries is associated with better growth, status of some micronutrients, cognitive performance, motor development and activity. Only three randomized trials supplemented children with milk and compared outcomes with a nonintervention control group. Both height and weight growth were improved, although in Kenya height was increased only in younger schoolers who were stunted at baseline. Meat supplements have been evaluated in only two randomized controlled trials, in Kenya and Guatemala (mean baseline age 8 years and 1 year, respectively); growth was no better than in an equicaloric control group. Meat improved cognitive function and activity in Kenya; milk was less effective than meat for improving cognitive function and physical activity, perhaps due to its lower content of iron, zinc, or riboflavin. Meat and especially cow's milk are excellent sources of vitamin B(12), a micronutrient commonly deficient in populations which consume low amounts of ASF. Other micronutrients such as iron have been added to cow's milk and resulted in improved nutritional outcomes for children.
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Dror DK, King JC, Durand DJ, Allen LH. Association of modifiable and nonmodifiable factors with vitamin D status in pregnant women and neonates in Oakland, CA. ACTA ACUST UNITED AC 2011; 111:111-6. [PMID: 21185972 DOI: 10.1016/j.jada.2010.10.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Accepted: 06/15/2010] [Indexed: 11/28/2022]
Abstract
There is little information on the contribution of modifiable vs nonmodifiable factors to maternal and neonatal vitamin D status in temperate regions of the United States. The purpose of this cross-sectional observation study conducted between December 2006 and February 2008 was to identify associations between observed and measured maternal characteristics and vitamin D status at term in pregnant women and their infants in a multiethnic community in Oakland, CA. Two hundred seventy-five pregnant women aged 18 to 45 years and carrying a singleton fetus were recruited and data from 210 mother-infant pairs were included in analyses. Analysis of covariance identified predictors of maternal and cord serum 25-hydroxyvitamin D [25(OH)D] in a multivariate model considering vitamin D intake, lifestyle factors, and skin pigmentation. Maternal serum 25(OH)D was significantly associated with season of delivery (P=0.0002), average daily D intake (P=0.0008), right upper inner arm pigmentation (P=0.0035), and maternal pre- or early-pregnancy body mass index (calculated as kg/m²) (P=0.0207). The same factors were significant for cord serum 25(OH)D, which was highly correlated with maternal serum 25(OH)D (r=0.79; P<0.0001). During the year, 54% of mothers and 90% of neonates had 25(OH)D <30 ng/mL (<75 nmol/L). Of women taking daily prenatal vitamin/mineral supplements (400 IU vitamin D), 50.7% had serum 25(OH)D <30 ng/mL (<75 nmol/L). In conclusion, 25(OH)D <30 ng/mL (<75 nmol/L) was prevalent in mothers and neonates across racial groups and seasons, and vitamin D status was associated with both modifiable and nonmodifiable risk factors.
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Thomas JE, Ou LT, Allen LH, Vu JC, Dickson DW. Improved soil fumigation by Telone C35 using carbonation. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2011; 46:655-661. [PMID: 21806461 DOI: 10.1080/03601234.2012.592048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Soil fumigation to control pests and pathogens is an important part of current agricultural practice. A reduction in fumigant emissions is required to ensure worker safety and environment health. A field trial in Florida was conducted to investigate whether carbonating Telone C35™ ((Z)- and (E)-1,3-dichloropropene with 35 % chloropicrin) would improve the delivery of the fumigant to such an extent that the application rate could be decreased without sacrificing efficacy. All treatments were carried out in three replications in a complete block design. The use of carbon dioxide (CO(2)) to carbonate and pressurize Telone C35 provided quicker and deeper distribution initially compared to application by nitrogen gas (N(2)) pressurization. The deeper distribution of Telone C35 components found with CO(2) application may have lowered the initial concentration of Telone C35, but it did not appreciably alter the disappearance rate of the three chemicals, chloropicrin, (Z)- and (E)-1,3-dichloropropene. The faster vertical distribution within the bedded soil of the Telone C35 by CO(2) did enhance volatilization of the active ingredients into the atmosphere compared to volatilization of similar reduced rate applied by N(2) pressurization. However, the cumulative amount volatilized from the carbonated fumigant beds at 75 % application rate was lower than the cumulative amount emitted by full rate of Telone C35 using N(2). The efficacy of the carbonated Telone C35 at a lower application rate was statistically equivalent to that of non-carbonated fumigant using N(2) pressurized injection at a higher application rate, based on weed enumeration and the root-knot nematode galling index.
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Dror DK, Allen LH. Vitamin D inadequacy in pregnancy: biology, outcomes, and interventions. Nutr Rev 2010; 68:465-77. [DOI: 10.1111/j.1753-4887.2010.00306.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Garrod MG, Miller JW, Calvert CC, Buchholz BA, Green R, Johnson HA, Allen LH. In vivo enrichment of chicken eggs with 14C‐B12 for determining vitamin B12 bioavailability in humans. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.915.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Anaya‐Loyola MA, Alvarez CS, Loria JLR, Allen LH. Low dietary intake of vitamina B12 predicts hyperhomocysteinemia in Mexican women. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.538.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Allen LH, Peerson JM. Impact of multiple micronutrient versus iron-folic acid supplements on maternal anemia and micronutrient status in pregnancy. Food Nutr Bull 2010; 30:S527-32. [PMID: 20120794 DOI: 10.1177/15648265090304s407] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Multiple micronutrient supplements could increase hemoglobin and improve micronutrient status of pregnant women more than iron supplements alone or iron with folic acid. OBJECTIVE To compare the effects of multiple micronutrients with those of iron supplements alone or iron with folic acid, on hemoglobin and micronutrient status of pregnant women. METHODS Studies were identified in which pregnant women were randomized to treatment with multiple micronutrients, or with iron with or without folic acid. A pooled analysis was conducted to compare the effects of these supplements on maternal hemoglobin, anemia, and micronutrient status. Effect size was calculated for individual and combined studies, based on mean change from baseline to final measure in the group receiving iron, with or without folic acid, minus the mean change in the group, divided by the pooled standard deviation of the two groups. The effect on the relative risk of anemia or iron deficiency was calculated as the probability of anemia or iron deficiency in the group receiving multiple micronutrients divided by the probability in the group receiving iron, with or without folic acid. RESULTS Multiple micronutrient supplements had the same impact on hemoglobin and iron status indicators as iron with or without folic acid. There was no overall effect on serum retinol or zinc. In the only study in which status of other micronutrients was analyzed, a high prevalence of multiple deficiencies persisted in the group receiving multiple micronutrients provided with daily recommended intakes of each nutrient. CONCLUSIONS Multiple micronutrient supplements increased hemoglobin synthesis to the same extent as supplementation with iron with or without folic acid, although often they contained lower amounts of iron. The amount of supplemental iron and other nutrients that can enable pregnant women with micronutrient deficiencies to achieve adequate status remains to be determined.
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Margetts BM, Fall CHD, Ronsmans C, Allen LH, Fisher DJ. Multiple Micronutrient Supplementation during Pregnancy in Low-Income Countries: Review of Methods and Characteristics of Studies Included in the Meta-Analyses. Food Nutr Bull 2009; 30:S517-26. [DOI: 10.1177/15648265090304s406] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This paper reports on the methods and characteristics of 12 studies from developing countries included in a meta-analysis of the impact of antenatal supplements of multiple micronutrients compared with iron–folic acid on micronutrient status, maternal nutritional status, birth outcomes, and neonatal survival.
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Miller JW, Garrod MG, Allen LH, Haan MN, Green R. Metabolic evidence of vitamin B-12 deficiency, including high homocysteine and methylmalonic acid and low holotranscobalamin, is more pronounced in older adults with elevated plasma folate. Am J Clin Nutr 2009; 90:1586-92. [PMID: 19726595 PMCID: PMC2777470 DOI: 10.3945/ajcn.2009.27514] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND An analysis of data from the National Health and Nutrition Examination Survey indicated that in older adults exposed to folic acid fortification, the combination of low serum vitamin B-12 and elevated folate is associated with higher concentrations of homocysteine and methylmalonic acid and higher odds ratios for cognitive impairment and anemia than the combination of low vitamin B-12 and nonelevated folate. These findings await confirmation in other populations. OBJECTIVE The purpose was to compare metabolic indicators of vitamin B-12 status, cognitive function, and depressive symptoms among elderly Latinos with elevated and nonelevated plasma folate. DESIGN Cross-sectional data were analyzed for 1535 subjects (age: >or=60 y) from the Sacramento Area Latino Study on Aging. Subjects were divided into 4 groups on the basis of plasma vitamin B-12 (< or >or=148 pmol/L) and folate (<or= or >45.3 nmol/L). Homocysteine, methylmalonic acid, holotranscobalamin, ratio of holotranscobalamin to vitamin B-12, Modified Mini-Mental State Examination, delayed recall, and depressive symptom scores were compared between the groups. RESULTS Individuals with low vitamin B-12 and elevated folate (n = 22) had the highest concentrations of homocysteine and methylmalonic acid and the lowest concentration of holotranscobalamin and ratio of holotranscobalamin to vitamin B-12 when compared with all other groups (P <or= 0.003). No differences in Modified Mini-Mental State Examination, delayed recall, and depressive symptom scores were observed between the low vitamin B-12 and elevated-folate group compared with other groups. CONCLUSIONS Low vitamin B-12 is associated with more pronounced metabolic evidence of vitamin B-12 deficiency when folate is elevated than when folate is not elevated. These data should be considered when assessing the potential costs, risks, and benefits of folic acid and vitamin B-12 fortification programs.
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Abstract
Assessment of micronutrient status is a major concern in public health nutrition, yet there are serious limitations to the indicators currently available. This paper presents the merits of these indicators along with their drawbacks, which include cost, lack of congruence between cutoffs denoting deficiency and adverse functional consequences, and inconsistent methods of evaluating the confounding effects of infections on micronutrient status indicators. Methods for assessing the functional consequences of micronutrient deficiencies are even less well developed; their usefulness would be enhanced by a greater focus on outcomes known to be influenced by deficiencies. Although there have been notable breakthroughs, further improvements in methods to assess micronutrient status are urgently needed.
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Lildballe DL, Hardlei TF, Allen LH, Nexo E. High concentrations of haptocorrin interfere with routine measurement of cobalamins in human serum and milk. A problem and its solution. Clin Chem Lab Med 2009; 47:182-7. [PMID: 19191724 DOI: 10.1515/cclm.2009.047] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Human milk and occasional serum samples contain high concentrations of unsaturated haptocorrin, which influence accurate measurement of cobalamins. METHODS Cobalamins in serum samples spiked with increasing amounts of unsaturated haptocorrin were measured employing the Centaur, Cobas and Architect analysers. Cobinamide-coated EAH sepharose was employed for pretreatment of the samples. Human milk samples were collected from 24 healthy mothers. Haptocorrin was measured by ELISA. RESULTS The measured concentration of cobalamins either increased (Centaur analyser) or decreased (Architect, Cobas analysers) significantly for haptocorrin >10 nM, and was 220%, 52% or 45% of the expected values in a serum sample containing 50 nM haptocorrin. Following pretreatment with cobinamide-sepharose, the expected cobalamin concentration was obtained (Centaur). The milk samples contained 4.5-180 nM haptocorrin. In samples containing >10 nM haptocorrin (n=19), the median concentration of cobalamins decreased from 1.3 nM to 0.67 nM after pretreatment with cobinamide-sepharose. CONCLUSIONS Haptocorrin in concentrations above 10 nM influences measurement of cobalamins giving rise to falsely elevated or decreased results. Removal of unsaturated haptocorrin by pretreatment with cobinamide-sepharose solves the problem.
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Allen LH, Peerson JM, Olney DK. Provision of multiple rather than two or fewer micronutrients more effectively improves growth and other outcomes in micronutrient-deficient children and adults. J Nutr 2009; 139:1022-30. [PMID: 19321586 DOI: 10.3945/jn.107.086199] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Deficiencies of multiple micronutrients (MMN) usually coexist in developing countries, but supplements have usually provided only 1 or 2 micronutrients (MN). To inform policy, in this article we compared the relative benefits of supplying MMN vs. a placebo or 1 or 2 MN on the following: children's growth, health, and development; pregnancy outcome; nutritional status; and HIV/AIDS mortality and morbidity in adults. Sufficient data were available to perform random-effects meta-analyses of randomized controlled trials (RCT) for the effects of MMN on child growth and nutritional status. Results for other outcomes are presented as effect sizes (ES) when available. In children, MMN interventions resulted in small but significantly greater improvements in length or height (ES = 0.13; 95% CI: 0.055, 0.21) and weight (ES = 0.14; 95% CI: 0.029, 0.25), hemoglobin (ES = 0.39; 95% CI: 0.25, 0.53), serum zinc (ES = 0.23; 95% CI: 0.18, 0.43), serum retinol (ES = 0.33; 95% CI: 0.050, 0.61), and motor development. A Cochrane review reported that compared with no supplementation or a placebo, MMN supplementation during pregnancy reduced the relative risk of low birth weight (0.83), small-for-gestational age (0.92), and anemia (0.61); however, MMN were not more effective than iron + folic acid alone. There is some evidence that MMN supplementation improves CD4 counts and HIV-related morbidity and mortality in adults. The efficacy of MMN varies across trials, but overall there is evidence that outcomes are better than when providing < or =2 MN. The policy implications of these studies are discussed.
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Olney DK, Kariger PK, Stoltzfus RJ, Khalfan SS, Ali NS, Tielsch JM, Sazawal S, Black R, Allen LH, Pollitt E. Development of nutritionally at-risk young children is predicted by malaria, anemia, and stunting in Pemba, Zanzibar. J Nutr 2009; 139:763-72. [PMID: 19225131 DOI: 10.3945/jn.107.086231] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Nutritionally at-risk children suffer delays in physical growth and motor and language development. Infectious diseases such as malaria pose an additional risk. We examined the cross-sectional relationships among malaria infection, hemoglobin (Hb) concentration, length-for-age Z-scores (LAZ), motor activity, behavior, and motor and language development in 841 Zanzibari children 5-19 mo old. We used structural equation modeling to test the fit of the data to a theoretical model and to examine the relationships among the variables in 3 age groups (5-9, 10-14, and 15-19 mo). The model fit the data for all age groups. In the youngest and oldest groups, children with higher malaria parasite densities had significantly lower Hb and LAZ. Higher LAZ significantly predicted higher total motor activity, and motor and language development scores in all age groups. In the oldest group, children who had higher Hb had higher motor development and activity scores. Malaria was directly and indirectly related to motor activity in the 10- to 14-mo-old group [standardized total effects, -0.14; direct, -0.10 (P = 0.015); and indirect, -0.038]. The significant fit of the models to the data and the statistical significance of many of the specific pathways highlight the complexities of the relationships between health and nutrition and child development outcomes in this population. In addition, the results suggest that multiple interventions are likely necessary to improve child development outcomes in this population of nutritionally at-risk children and that the potential effectiveness of interventions may differ according to age (i.e. prevention and treatment of anemia, stunting, and malaria).
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Miller JW, Garrod MG, Allen LH, Haan MN, Green R. Elevated plasma folate in older adults is associated with more pronounced evidence of vitamin B12 deficiency, including high homocysteine and methylmalonic acid and low holotranscobalamin. FASEB J 2009. [DOI: 10.1096/fasebj.23.1_supplement.335.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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145
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Green R, Lee K, Sutter S, Allen LH, Buchholz B, Dueker SR, Miller JW. Evidence that physiological doses of vitamin B12 are metabolized or degraded in the gastrointestinal tract: implications for vitamin B12 bioavailability and fortification. FASEB J 2009. [DOI: 10.1096/fasebj.23.1_supplement.335.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
In considering the vitamin B-12 fortification of flour, it is important to know who is at risk of vitamin B-12 deficiency and whether those individuals would benefit from flour fortification. This article reviews current knowledge of the prevalence and causes of vitamin 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 vitamin B-12 deficient (plasma vitamin B-12 < 148 pmol/L), with the prevalence of deficiency increasing with age. Closer to 20% have marginal status (plasma vitamin 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 vitamin B-12 in younger adults and likely the main cause in poor populations worldwide; in most studies, serum vitamin B-12 concentration is correlated with intake of this vitamin. 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 vitamin from fortified food. Fortification of flour with vitamin B-12 is likely to improve the status of most persons with low stores of this vitamin. 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.
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McLean E, de Benoist B, Allen LH. Review of the magnitude of folate and vitamin B12 deficiencies worldwide. Food Nutr Bull 2008; 29:S38-51. [PMID: 18709880 DOI: 10.1177/15648265080292s107] [Citation(s) in RCA: 175] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Human deficiencies of folate and vitamin B12 result in adverse effects which may be of public health significance, but the magnitude of these deficiencies is unknown. Therefore, we examine the prevalence data currently available, assess global coverage of surveys, determine the frequency with which vitamin status assessment methods are used, and identify patterns of status related to geographical distribution and human development. Surveys were identified through PubMed and the Vitamin and Mineral Nutrition Information System at the World Health Organization (WHO). Since different thresholds were frequently used to define deficiency, measures of central tendency were used to compare blood vitamin concentrations among countries. The percentage of countries with at least one survey is highest in the WHO Regions of South-East Asia and Europe. Folate and vitamin B12 status were most frequently assessed in women of reproductive age (34 countries), and in all adults (27 countries), respectively. Folate status assessment surveys assessed plasma or serum concentrations (55%), erythrocyte folate concentrations (21%), or both (23%). Homocysteine was assessed in one-third of the surveys of folate and vitamin B12 status (31% and 34% respectively), while methylmalonic acid was assessed in fewer surveys of vitamin B12 status (13%). No relationship between vitamin concentrations and geographical distribution, level of development, or population groups could be identified, but nationally representative data were few. More representative data and more consistent use of thresholds to define deficiency are needed in order to assess whether folate and vitamin B12 deficiencies are a public health problem.
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Allen LH. Priority areas for research on the intake, composition, and health effects of tree nuts and peanuts. J Nutr 2008; 138:1763S-1765S. [PMID: 18716183 DOI: 10.1093/jn/138.9.1763s] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This article summarizes the main conclusions drawn from a conference on the health effects of nut consumption and identifies priority areas for future research. Individuals with higher intakes of nuts generally have higher intakes of many beneficial dietary constituents. More information is needed on nut composition, the bioavailability of nutrients, and other bioactive constituents. Better methods are needed to assess usual nut intake, including biomarkers, and the types, physical form, and amounts of nuts that are consumed. The feasibility of including nuts and seeds as a separate food group in the Dietary Guidelines should be tested, as should ways to increase nut intake. A moderate intake of nuts can be included in a weight loss regimen and further information is needed on whether nuts improve satiety as well as adherence to and efficacy of diets designed for weight reduction. There is substantial evidence that nut consumption reduces risk of cardiovascular disease. Future research should investigate their benefits for prevention of congestive heart failure, including clinical studies in patients with this condition, to evaluate the effects of nuts on markers of heart disease risk. Higher nut consumption is associated with lower risk of diabetes and associated cardiovascular disease. More remains to be learned about the effects of nuts on postprandial glycemic and insulin response, glycemic control, and improvement of disease risk factors in subjects with prediabetes and diabetes. Information is needed on nut-induced allergic reactions, including their prevalence and consequences, causes of sensitization, biomarkers of severe reactions, and cross-reactivity to different types of nuts.
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149
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Dror DK, Allen LH. Effect of vitamin B12 deficiency on neurodevelopment in infants: current knowledge and possible mechanisms. Nutr Rev 2008; 66:250-5. [PMID: 18454811 DOI: 10.1111/j.1753-4887.2008.00031.x] [Citation(s) in RCA: 264] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Severe vitamin B(12) deficiency produces a cluster of neurological symptoms in infants, including irritability, failure to thrive, apathy, anorexia, and developmental regression, which respond remarkably rapidly to supplementation. The underlying mechanisms may involve delayed myelination or demyelination of nerves; alteration in the S-adenosylmethionine:S-adenosylhomocysteine ratio; imbalance of neurotrophic and neurotoxic cytokines; and/or accumulation of lactate in brain cells. This review summarizes the current knowledge concerning infantile vitamin B(12) deficiency, including a pooled analysis of case studies of infants born to mothers with untreated pernicious anemia or a strict vegetarian lifestyle and a discussion of the mechanisms that may underlie the manifestations of deficiency.
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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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