维生素C、B_6和牛磺酸增强叶酸防畸效果的观察

目的　观察维生素 C、B6和牛磺酸对叶酸防畸效果的影响。方法　以环磷酰胺致胎鼠发育畸形动物模型 ,分别对孕鼠补充叶酸 ;叶酸 +VC+VB6+牛磺酸 ,观察防畸效果。结果　补充上述营养素者可使胎鼠脑膨出率下降 (P<0 .0 1 ) ,胎鼠平均体重增加 (P<0 .0 5 ) ,上枕骨骨化程度提高 (P<0 .0 1 )。补充叶酸 +VC+VB6+牛磺酸组 ,与单独补充叶酸组比较 ,脑膨出率降低明显 (P<0 .0 5 ) ,上枕骨骨化程度提高 (P<0 .0 1 )。结论　叶酸有明显的促进胚胎发育和拮抗环磷酰胺致畸的作用 ,且与 VC、VB6及牛磺酸联合应用的效果明显优于单独补充。     

维生素E及叶酸对高血糖孕鼠子代心肌细胞凋亡的影响

目的探讨维生素E(Ve)及叶酸对高血糖诱导的乳鼠心肌细胞凋亡蛋白caspase-3表达的影响。方法将50只清洁级成年SD孕鼠随机分为5组,分别为正常对照组(A组)、妊娠糖尿病组(B组)、叶酸组(C组)、维生素E组(D组)和Ve+叶酸组(E组)。除对照组外,其余大鼠于妊娠d 1腹腔注射链脲佐菌素(STZ)35 mg/kg制备妊娠糖尿病动物模型,对照组给予等量0.1 mmol/L(p H 4.5)柠檬酸钠—柠檬酸缓冲液。孕d 5,D、E 2组予50 mg/kg维生素E灌胃,C、E组予0.4 mg/kg叶酸灌胃,A、B组予等量的生理盐水灌胃,持续7 d。取自然分娩的乳鼠心肌组织于光镜下观察心肌结构的改变,应用免疫组织化学法检测各组乳鼠心肌细胞caspase-3抗原的表达。蛋白免疫印迹(western-blot)检测各组乳鼠心肌细胞caspase-3的表达。结果 (1)造模前各组血糖值比较差异无统计学意义(P>0.05);造模后,B、C、D、E组血糖值明显高于A组,差异有统计学意义(P<0.01);B、C、D、E 4组间比较差异无统计学意义(P>0.05)。(2)光镜下观察B、C、D、E组乳鼠心肌组织呈现不同程度损伤,表现为细胞坏死、水肿、轮廓不清,心肌纤维排列疏松紊乱、炎性细胞浸润。(3)5组乳鼠心肌细胞凋亡蛋白caspase-3的表达不同,差异有统计学意义(P<0.01)。结论妊娠糖尿病孕鼠对子代心肌细胞凋亡影响明显,孕期补充维生素E、叶酸对乳鼠心肌细胞凋亡有明显改善作用,且叶酸抑制凋亡的作用优于维生素E,同时补充维生素E和叶酸的效果优于单独补充一种。     

维生素A缺乏及补充对大鼠胚胎存活及后脑Hoxa-2和Hoxb-2基因表达的影响

目的:研究维生素A(VA)缺乏及补充对大鼠胚胎后脑Hoxa-2和Hoxb-2mRNA表达的影响。方法:初断乳SD雌性大鼠60只,按体重随机分为VA缺乏组(A),VA缺乏妊娠0d(E0)补充组(B)和正常对照组(N)。A组和B组喂饲VA缺乏饲料,B组自E0天起改喂VA补充饲料(含VA10000IU/kg饲料),N组喂饲VA充足饲料(含VA4000IU/kg饲料),雄鼠饲以普通饲料。喂饲7w后采集尾血,将雌雄大鼠2︰1合笼交配,分别于妊娠D12.5(E12.5)和妊娠D19.5(E19.5)将孕鼠处死,留取血标本,剖腹取出胚胎。用微量荧光法测定母鼠血清中VA含量;观察E12.5和E19.5胚胎存活情况,记录活胎数、死胎数及吸收胎数;并用半定量逆转录聚合酶链反应(RT-PCR)检测E12.5胚胎组织Hoxa-2、Hoxb-2mRNA的表达。结果:与N组相比,A组孕鼠血清VA水平下降;E12.5和E19.5胚胎的存活率显著降低,死胎及吸收胎的发生率增加,E12.5胚胎Hoxa-2、Hoxb-2mRNA表达水平明显下降;B组孕鼠各项指标同正常组相比无显著性差异。结论:胚胎后脑发育基因Hoxa-2、Hoxb-2可能介导VA对大鼠胚胎存活的影响。     

补充维生素A和铁对孕妇铁营养状况的影响

目的　研究补充维生素 A、铁对孕妇铁营养状况的影响。方法　对 1 6 7名孕中期妇女进行铁和维生素 A营养状况的横断面调查并随机分成 4组 :对照组 (复合维生素 B片每日一片 ) ;补充维生素 A组 (1 1 0 0 μg/d) ;补充铁组 (6 0 mg/d元素铁 ) ;补充维生素 A和铁组 (VA1 1 0 0μg/d,Fe6 0 mg/d) ,共补充 1 0 w。结果　被调查孕妇孕中期维生素 A轻度缺乏率为 0 .6 % ,贫血患病率为 7.8% ,贮存铁缺乏率为 6 .2 %。血清 VA水平补充前各组正常 ,补充后对照组明显下降 ,但仍维持在正常范围。补 VA、补铁及补 VA+铁组血清 VA与补充前无明显差异 ,仍保持恒定。各组补充前后 Hb均在正常范围 ,差别不显著。血清铁蛋白、游离红细胞原卟啉及运铁蛋白饱和度补充后的改善效果均以补充 VA铁组优于单独补 VA或补铁组。结论　孕期同时补充 VA和铁对改善铁的营养状况优于单纯补铁。     

维生素AE缺乏与儿童呼吸道感染的相关性和补充维生素AE后免疫状态与安全性分析*

目的观察儿童维生素A、E缺乏与呼吸道感染的相关性和补充治疗儿童呼吸道感染的疗效与安全性。方法选取128例反复呼吸道感染患儿,随机分为常规组和联合组。常规组给予常规抗感染治疗,联合组则额外给予补充维生素A、E治疗,50例健康儿童设为对照组。观察三组儿童血清维生素A、E和免疫球蛋白水平,分析维生素A、E缺乏与反复呼吸道感染的相关性,评价临床治疗效果,比较不良反应及复发率。结果 128例患儿维生素A、E缺乏检出率分别为86.72%和48.44%,明显高于健康儿童(6.00%和4.00%),组间差异比较(P0.05);维生素A、E缺乏均和儿童反复呼吸道感染呈明显的负相关;联合组治疗后血清维生素A、E水平及血清IgA、IgG和IgM水平高于常规组(P0.05);常规组和联合组临床治疗显效率分别为76.56%和92.19%(P0.05);联合组患儿发热、咳嗽、扁桃体肿大和肺部啰音症状消失时间均短于常规组(P0.05);常规组和联合组随访1年复发率分别为21.86%和6.25%(P0.05)。结论维生素A、E缺乏可增加反复呼吸道感染的发生风险,补充维生素A、E可提高临床疗效,改善患儿免疫功能,降低复发率,安全可靠。     

大豆异黄酮与叶酸对大鼠神经管畸形的保护作用

目的　研究大豆异黄酮的抗氧化作用及其与叶酸配伍对大鼠神经管畸形的保护性作用。方法　以环磷酰胺制备大鼠神经管畸形的模型 ,生理盐水作对照组 ,另外设单独叶酸组、叶酸配伍大豆异黄酮共 5个干预组 (叶酸的量固定不变 ) ,分别进行抗氧化指标、胎鼠畸形发生率、生长发育指标和光镜及透射电镜的检测。结果　 ( 1)干预组较模型组孕鼠血清SOD含量增加、MDA含量降低 ,NO含量有所下降 ,且与大豆异黄酮有剂量 -反应关系 ;( 2 )胎鼠大体形态结果显示 ,干预实验组胎鼠脑膨出发生率较模型组均有下降 ,并以 40mg/ (kg·bw)的大豆异黄酮配伍叶酸组下降最明显 ;( 3)干预组胎鼠的各项生长发育指标均较模型组有所增长或增重 ;( 4)光镜病理切片显示 ,干预组细胞碎片和小群凋亡细胞聚集的现象较模型组明显减少 ;( 5 )透射电镜结果可以看见细胞凋亡的严重程度以及凋亡细胞的数量较模型组有明显改善。结论　大豆异黄酮在一定剂量时与叶酸配伍可以较单独补充叶酸更为有效地预防大鼠神经管畸形的发生。     

联合检测妊娠早期血清维生素A、E水平对子痫前期的预测价值

目的探讨妊娠早期血浆维生素A、E水平联合检测对子痫前期(PE)的预测价值。方法选取2015年5月-2016年12月在首都医科大学电力教学医院进行产检的孕妇2 788例,发生子痫前期孕妇116例,其中轻度PE孕妇65例作为轻度PE组,重度PE孕妇51例作为重度PE组,以正常妊娠孕妇100例作为对照组。分别于孕≤13周采集血清,采用高效液相色谱法测定血清维生素A、E含量。结果重度PE组维生素A、E水平及维生素A、E水平中位数倍数(MOM值)明显低于轻度PE组(P0.05),轻度PE组维生素A、E水平及维生素A的MOM值明显低于对照组(P0.05),而维生素E的MOM值与对照组差异无统计学意义(P0.05);血清维生素A(MOM值)的ROC曲线下面积为0.204(95%CI:0.146~0.261,P0.05);血清维生素E的ROC曲线下面积为0.258(95%CI:0.192~0.324,P0.05);两者联合检测ROC曲线下面积为0.201(95%CI:0.144~0.258,P0.05),灵敏度41%,特异度11%。结论 PE孕妇血清维生素A、E水平降低,可能与PE的发病有关,单独或联合检测维生素A、E,敏感性及特异性较低,对预测PE的价值有限。     

各妊娠时期孕妇血清维生素A和维生素E水平分析

目的维生素A和维生素E在参与机体生长发育和维持机体正常生理功能方面发挥非常重要的作用,孕妇妊娠期血容量增大,对各种必要维生素需求量也随着妊娠进展而增加。本研究分析本地区妊娠早期、中期及晚期孕妇血清维生素A和维生素E水平,为孕妇补充必要维生素及优生优育提供理论依据。方法选取2017-01-01-2017-12-31绵阳市中心医院产科门诊常规产检孕妇766例,采用高效液相色谱-质谱联用法检测血清维生素A和维生素E水平。结果 766例孕妇血清维生素A水平为(413.5±231.2)ng/mL,血清维生素E水平为(12.7±5.7)μg/mL,血清维生素A总体异常173例(22.6%),其中缺乏69例(9.0%),偏低104例(13.6%),未检出过量状态孕妇;血清维生素E总体异常139例(18.1%),其中缺乏9例(1.2%),偏低130例(17.0%),未检出过量状态孕妇。不同孕期组维生素A(F=7.117,P=0.001)、维生素E水平(F=9.346,,P0.001)比较,差异有统计学意义;不同年龄组维生素A(F=0.415,P=0.742)、维生素E水平(F=0.700,P=0.552)比较,差异无统计学意义。结论不同孕期维生素A和维生素E水平差异明显,本地区维生素A和E均以缺乏为主,因此重视孕期维生素A和E水平监测,合理正确补充必要维生素,对保障母婴健康有重要意义。     

维生素E对手机辐射致孕鼠及胎鼠脑组织损伤的干预作用

目的研究妊娠期补充维生素E对受手机辐射后产生损伤的母鼠及胎鼠脑组织的保护作用。方法 40只清洁级受孕大鼠随机分为5组(阳性对照组,阴性对照组,维生素E低、中、高剂量组)。自妊娠第1天起,维生素E低、中、高剂量组孕鼠分别按5、15和30mg/ml的剂量补充维生素E花生油溶液,阴性对照组和阳性对照组灌服脱维生素E的花生油,同时用辐射频率900MHz手机对阳性对照组和高、中、低剂量组给予1h/次,3次/d的手机辐射处理,连续辐射21d。分娩后取胎鼠右侧海马组织电镜观察胎鼠脑组织中海马区神经细胞损害程度。测定孕鼠及胎鼠脑组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)的含量。结果与阴性对照组相比,阳性对照组胎鼠脑组织中可见神经元、神经胶质细胞线粒体肿胀,毛细血管周围轻微水肿,核染色质浓缩、边集,血管内皮细胞有空泡形成。中、高剂量组神经细胞和毛细血管异常现象不如阳性对照组的明显。高剂量组神经元可见核染色质均匀,胞质内富含线粒体、粗面内质网和大量的游离核糖体。全部切片未见神经细胞凋亡。在抗氧化酶活性实验中,阳性对照组与阴性对照组相比,母鼠和胎鼠脑组织中SOD、GSH-Px活性明显降低,MDA的含量显著升高,且均有统计学意义(P<0.05)。与阳性对照组相比较,维生素各剂量组的胎鼠脑组织中SOD、GSH-Px的活性均升高,且中、高剂量组MDA含量均降低。高剂量组母鼠脑组织中SOD、GSH-Px的活性明显升高,MDA含量明显降低(P<0.05)。中剂量组母鼠脑组织中SOD的含量较阳性对照组亦有明显升高(P<0.05)。并且随着剂量的增加SOD、GSH-Px的活性具有升高的趋势,MDA含量有下降的趋势。结论在一定的剂量下,维生素E对手机辐射所致胎鼠海马区神经细胞和毛细血管异常具有一定的保护作用,对孕鼠及胎鼠脑组织所产生的抗氧化系统的损害具有保护作用。     

黄芩黄酮与维生素E对染尘小鼠肺损伤的保护作用

目的探讨黄芩黄酮与维生素E单独与联合应用对染尘小鼠肺损伤过程中SOD活性、MDA、LDH以及Hyp含量的影响。方法采用气管注入法给予二氧化硅混悬液(SiO2)建立染尘鼠模型。建模1周后按照2×2析因设计将实验动物分为模型对照组A,黄芩黄酮干预组B,维生素E干预组C,黄芩黄酮与维生素E联合干预组D,并设正常对照组N。给药2周后分别测定各组的SOD活性、MDA、LDH以及Hyp的含量。结果与模型对照组比较,黄芩黄酮组、维生素E组、黄芩黄酮与维生素E联合组均能提高SOD活性,可有效减少MDA的产生(P0.05),黄芩黄酮与维生素E联合组的效果较单独应用效果明显;黄酮黄芩与维生素E联合能明显减少Hyp、LDH的含量及肺体重指数(P0.05)。结论黄芩黄酮与维生素E有交互作用,能提高小鼠SOD的活性,减少LDH、脂质过氧化反应物以及Hyp的生成,对肺损伤有更好的保护作用。     

叶酸和维生素B_(12)联合抗酒精发育毒性的实验研究

目的:研究叶酸(FA)和维生素B12(VB12)联合抗酒精发育毒性的效果。方法:以5g/kg乙醇灌胃孕D6～D15的ICR小鼠建立酒精发育毒性动物模型,于孕D1～D16每天按三个组别分别灌胃FA60mg/kgbw、VB121mg/kg、FA60mg/kgbw+VB121mg/kgbw,设酒精模型组和阴性对照组,所有动物于孕D18剖杀观察。结果:与酒精模型组比较,FA和VB12联合干预组孕期母鼠增重下降现象明显改善,活胎率显著增加,活胎体重、身长、尾长均显著增加,胸骨、枕骨、四肢骨骨化异常发生率显著下降(P<0.01),尾椎骨骨化点数显著增加(P<0.01);FA单独干预组上述发育毒性表现也有一定程度的改善,但不如联合组;VB12单独干预组的预防作用不明显。结论:FA和VB12联合干预对酒精的发育毒性具有预防控制作用。     

Dietary vitamin C and folic acid supplementation ameliorates the detrimental effects of heat stress in Japanese quail

We evaluated the effects of vitamin C (L-ascorbic acid) and folic acid supplementation on performance, carcass characteristics and concentrations of the oxidative stress markers [malondialdehyde (MDA), homocysteine], adrenocorticotropic hormone (ACTH), vitamins C, E, A, B-12 and folic acid, and mineral status in broiler Japanese quail (Coturnix coturnix japonica) exposed to high ambient temperature (34 degrees C, 8 h/d, 0900-1700 h). The birds (n = 150; 10-d-old) kept at 34 degrees C were fed a basal diet (HS group) or the basal diet supplemented with 250 mg of L-ascorbic acid/kg of diet (Vit C group), 1 mg of folic acid/kg of diet (FA group) or both (Vit C + FA group), whereas birds kept at 22 degrees C were fed the basal diet (TN group). Supplementing heat-stressed quail with vitamin C and folic acid improved performance compared to the HS group. Effects generally were greatest in quail supplemented with both. Although supplementation did not consistently restore concentrations to those of the TN group, it increased serum concentrations of the vitamins under study. Furthermore, serum and tissue MDA, homocysteine and ACTH concentrations were lower in the supplemented groups than in the heat-stressed controls. Retention of N, ash, Ca, P, Zn, Fe, Cu and Cr were highest in the Vit C + FA group and lowest in the HS group (P < 0.05). The results of the study indicate that vitamin C and folic acid supplementation attenuates the decline in performance and antioxidant status caused by heat stress. Such supplementation may offer protection against heat stress-related depression in performance of Japanese quail.     

Folic acid supplementation for 4 weeks affects liver morphology in aged rats

Several countries have approved universal folic acid (FA) fortification to prevent neural tube defects and/or high homocysteine levels; this has led to a chronic intake of FA. Traditionally, the vitamin is considered to be safe and nontoxic, except for the potential masking of vitamin B-12 deficiency. Recent reports from our laboratories showed several effects of high-dose folate supplementation in rats. In this work, we compared the effect of FA on the liver of weanling (3 wk) and aged (18 mo) male rats fed either a diet supplemented with 40 mg FA/kg diet or a control diet (1 mg FA/kg diet) for 4 wk. FA supplementation did not alter serum aspartate aminotransferase, alanine aminotransferase, urea, glucose oxidase, total bilirubin, or uric acid. Routine histological staining as well as immunohistochemistry with proliferating cell nuclear antibody for dividing cells, and cytokeratin-8 against bile ductal cells, showed that aged, supplemented rats had the same number of hepatocytes as both control and supplemented weanling rats, and tended to have more (17%, P = 0.07) hepatocytes than aged, control rats. Moreover, the bile duct cells of aged, control rats proliferated and transformed into cholestatic rosettes at a higher frequency than in aged, supplemented rats. The morphology of the liver in weanling rats was similar in both diet groups, and comparable to the supplemented, aged rats, thus indicating that a high intake of FA improves normal liver morphology in livers of aged rats.     

Folic acid supplements in pregnancy and birth outcome: re-analysis of a large randomised controlled trial and update of Cochrane review

Periconceptual folic acid prevents neural tube defects. The effect of folic acid taken throughout pregnancy is unclear, however. We re-analysed data from a large randomised controlled trial performed between 1966 and 1967 and combined the results with those from trials included in a Cochrane review. A total of 2928 women were randomised: 1977 were allocated to placebo, 466 to folic acid 200 microg/day and 485 to folic acid 5 mg/day. Folic acid supplementation was not associated with any difference in mean birthweight, placental weight or gestational age. When combined with trials in the Cochrane review folic acid at high doses was associated with reduced risk of low birthweight (pooled relative risk 0.73 [95% CI 0.53, 0.99]). We found no conclusive evidence of benefit for folic acid supplementation in pregnant women given from time of booking onwards.     

Vitamin A and iron supplementation of Indonesian pregnant women benefits vitamin A status of their infants.

Many Indonesian infants have an inadequate nutritional status, which may be due in part to inadequate maternal nutrition during pregnancy. This study was designed to investigate whether infant nutritional status could be improved by maternal vitamin A and Fe supplementation during gestation. Mothers of these infants from five villages had been randomly assigned on an individual basis, supervised and double-blind, to receive supplementation once weekly from approximately 18 weeks of pregnancy until delivery. Supplementation comprised 120 mg Fe and 500 microg folic acid with or without 4800 retinol equivalent vitamin A. Mothers of infants from four other villages who participated in the national Fe and folic acid supplementation programme were also recruited; intake of tablets was not supervised. Anthropometric and biochemical parameters of infants and their mothers were assessed approximately 4 months after delivery. Infants of mothers supplemented with vitamin A plus Fe had higher serum retinol concentrations than infants of mothers supplemented with Fe alone. However, the proportion of infants with serum retinol concentrations <0.70 micromol/l was >70 % in all groups. Maternal and infant serum retinol concentrations were correlated. Fe status, weight and length of infants were similar in all groups. Fe status of girls was better than that of boys, but boys were heavier and longer. We conclude that supplementation with vitamin A in conjunction with Fe supplementation of women during pregnancy benefits vitamin A status of their infants. However, considering the large proportion of infants with marginal serum retinol concentrations, it may still be necessary to increase their vitamin A intake.     

The effects of maternal folic acid and vitamin C nutrition in early pregnancy on reproductive performance in the guinea-pig

1. The effect of different intakes of folic acid (FA) and vitamin C on pregnancy in the Dunkin-Hartley guinea-pig was examined. Female guinea-pigs were subjected to three graded intakes of FA and vitamin C ('deficient', 'intermediate' similar to recommended daily intakes (RDI), and 'supplemented') during early gestation and up to the time of neural tube closure (17th day of gestation), and then returned to the RDI of these vitamins. 2. Plasma and blood cell concentrations of these vitamins were measured once before and at the end of the dietary treatments. Reproductive performance was assessed in terms of the number of resorbed and aborted embryos and weight and size of the live fetuses on the 36th day of gestation. 3. The short-term deficiency of either of these two vitamins, insufficient to affect maternal health, had a dramatic effect on the reproductive performance. 4. The RDI of FA was significantly less effective than the supplemented intake in preventing embryonic deaths. The RDI of vitamin C produced lighter and smaller live fetuses than the supplemented intake. 5. The implications of these findings with regard to vitamin status in early pregnancy in man are discussed.     

Folic acid and vitamin B12 are more effective than vitamin B6 in lowering fasting plasma homocysteine concentration in patients with coronary artery disease

OBJECTIVE: To investigate whether vitamin B(6) supplementation had a beneficial effect on lowering fasting plasma homocysteine concentrations in coronary artery disease (CAD) patients. DESIGN: A single-blind intervention study. SETTING: The study was performed at the Taichung Veterans General Hospital, the central part of Taiwan. SUBJECTS: A total of 50 subjects were identified by cardiac catheterization to have at least 70% stenosis of one major coronary artery. In all, 42 patients successfully completed this study. INTERVENTIONS: Patients were randomly assigned to one of five groups and treated with a daily dose of placebo (n=8), 5 mg vitamin B(6) (n=8), 10 mg vitamin B(6) (n=8), 50 mg vitamin B(6) (n=9), or 5 mg folic acid combined with 0.25 mg vitamin B(12) (n=9) for 12 weeks. MAIN OUTCOME MEASURES: Nutrient intakes were recorded by using 24-h diet recalls when patients returned to the cardiology clinic before the intervention (week 0) and at week 12. Vitamin B(6) status was assessed by direct measures (plasma pyridoxal 5'-phosphate) and indirect measures (erythrocyte alanine and aspartate aminotransaminase activity coefficient). Fasting plasma homocysteine, serum folic acid, and vitamin B(12) were measured. RESULTS: Fasting plasma homocysteine concentration did not respond to high or low doses of vitamin B(6) when compared with a placebo treatment after 12 weeks of supplementation. The mean fasting plasma homocysteine concentration, however, decreased significantly after 12 weeks of folic acid combined with vitamin B(12) supplementation (P=0.047). Further, within group, mean fasting plasma homocysteine concentration was nonsignificantly increased by 25.5, 16.2, and 18.3% in placebo, 10 mg/day and 50 mg/day vitamin B(6) supplemented groups, respectively; whereas folic acid combined with vitamin B(12) supplementation significantly reduced fasting plasma homocysteine concentration by 32% (P<0.001). CONCLUSIONS: Our results indicate that vitamin B(6) supplementation alone is less effective than folic acid combined with vitamin B(12) in lowering plasma homocysteine concentrations in CAD patients. SPONSORSHIP: This study was supported by the National Science Council, Taiwan, Republic of China (NSC-91-2320-B-040-023).     

Weekly may be as efficacious as daily folic acid supplementation in improving folate status and lowering serum homocysteine concentrations in Guatemalan women

Daily folic acid (FA) supplementation improves folate status, lowers circulating homocysteine (Hcy) concentrations, and reduces the risk of neural tube defects. Little is known about the efficacy of weekly FA supplementation. The objective of this study was to compare the efficacy of weekly and daily FA supplementations in improving folate and vitamin B-12 status and lowering Hcy concentrations in healthy reproductive-aged women. A randomized, double-blind supplementation trial was conducted in Guatemala. A total of 459 women were assigned randomly to 4 groups to receive weekly (5000 or 2800 microg) or daily (400 or 200 microg) FA for 12 wk. Daily and weekly iron, zinc, and vitamin B-12 were also provided. We determined serum and RBC folate by microbiological assays, but the latter was available only at baseline. Serum Hcy and vitamin B-12 were also measured. We used generalized linear regression models to assess the effects of treatment on biochemical indicators. Supplementation improved folate status similarly across all 4 groups. Overall, mean serum folate concentrations increased by 15.4 nmol/L (95% CI: 13.8, 16.9) and the geometric mean serum Hcy concentration decreased by 9.8% (95% CI: -12.3, -7.1). Daily supplementation improved serum vitamin B-12 by 20% (95% CI: 8, 33.2), whereas weekly supplementation had no effect. In conclusion, weekly FA (either high or low dose) plus vitamin B-12 may be as efficacious as daily supplementation in improving serum folate and lowering Hcy concentrations in healthy women of reproductive age.     

High prevalence of folic acid and vitamin B12 deficiencies in infants, children, adolescents and pregnant women in Venezuela

BACKGROUND: There is increased worldwide concern about the consequences of folic acid and vitamin B12 deficiencies on health, which include megaloblastic anemia, neural tube defects and cardiovascular disease. OBJECTIVE: This study intended to determine the prevalence of folic acid and vitamin B12 deficiencies in vulnerable groups in labor and poor socioeconomic strata of the Venezuelan population. METHODS: A total of 5658 serum samples were processed to determine folic acid and vitamin B12 concentrations. The study involved three surveys performed during 2001-2002 and included infants, children, adolescents and pregnant women from labor and poor socioeconomic strata of the population. The method used was a radio immunoassay designed for the simultaneous measurement of serum folic acid and vitamin B12. RESULTS: The prevalence of folic acid deficiency was higher than 30% for all groups studied, reaching 81.79% in adolescents. Vitamin B12 deficiency was 11.4% in samples collected nationwide, but there was also a similar prevalence of high serum levels. The prevalence of folic acid and vitamin B12 deficiencies in pregnant women reached 36.32 and 61.34%, respectively. CONCLUSION: This work shows that there is a high prevalence of folic acid deficiency, especially in women of reproductive age, pregnant adolescents and in the whole population studied in Vargas state. This situation requires immediate intervention as supplementation or food fortification programs.