Homocysteine lowering effect of different multivitamin preparations in patients with end-stage renal disease.

OBJECTIVE: Hyperhomocysteinemia occurs in nearly 100% of patients with end-stage renal disease (ESRD) and is associated with increased morbidity and mortality. Means to reduce elevated homocysteine concentrations is supplementation with folic acid, vitamin B6, and vitamin B12. However, doses of vitamins required for optimized treatment are subject of debate. Therefore, the effect of 2 different multivitamin preparations on the homocysteine concentrations in patients with ESRD were compared. DESIGN: Patients received 3 times per week either 2 tablets of preparation A (800 microg folic acid, 6 microg vitamin B12, 10 mg vitamin B6), 2 tablets of preparation B (160 microg folic acid, no vitamin B12, 10 mg vitamin B6), or placebo for a period of 12 weeks with control of total homocysteine (tHcy) levels at baseline, and at 4, 8, and 12 weeks. SETTING: The study was performed at the University Hospital of Magdeburg, Germany in patients with ESRD treated with chronic intermittent maintenance hemodialysis. RESULTS: Preparation A reduced the tHcy concentration significantly by nearly 50%, whereas preparation B did not change the tHcy concentration in comparison with placebo. However, tHcy was not normalized in the majority of patients receiving preparation A. CONCLUSION: The reduction of tHcy achieved by a multivitamin containing 800 microg folic acid was substantial and even higher than the reduction reported in supplementation studies using higher doses of folic acid alone. Nevertheless, hyperhomocysteinemia in ESRD patients appears relatively refractory to vitamin supplementation, in contrast with results obtained in healthy volunteers.     

Vitamin intake in Japanese women college students

The Standard Food Tables of Japanese Foods was newly revised in 2000, and contains information on all of the vitamins except biotin. Thus, we carried out a survey of vitamin intake in Japanese women who were university seniors majoring a dietitian course. The subjects (n = 33) consumed self-selected foods, and food intake was recorded by the weight method. We calculated the vitamin intake except for biotin from the food records using the Standard Food Tables of Japanese Foods. In terms of daily intake, vitamin A was 705+/-435 microg (mean+/-SD), vitamin D 6+/-8 microg, vitamin E 7.7+/-3.0 mg, vitamin K 191+/-156 microg, vitamin B1 0.7+/-0.3 mg (0.43+/-0.15 mg/1,000 kcal), vitamin B2 1.1+/-0.4 mg (0.65+/-0.18 mg/1,000 kcal), vitamin B6 0.9+/-0.4 mg (0.017+/-0.005 mg/g protein), vitamin B12 4.4+/-4.1 microg, niacin equivalent 23+/-7 mg (14.4+/-4.9 mg/1,000 kcal), pantothenic acid 4.6+/-1.4 mg, folic acid 267+/-115 microg, and vitamin C 73+/-38 mg. All of these averages were around the Japanese Recommended Dietary Allowance (RDA) for level "III (preferable)" of physical activity. Major vitamin A resources were vegetables; vitamin D resources, fish; vitamin E resources, fats and oils and vegetables; vitamin K resources, vegetables; vitamin B1 resources, cereals and animal meats; vitamin B2 resources, various foods; vitamin B6 resources, cereals, vegetables, fish, and animal meats; vitamin B12 resources, fish; niacin equivalent resources, fish, animal meats, and cereals; pantothenic acid resources, various foods; folic acid resources, vegetables; and vitamin C resources, vegetables and potatoes. From this survey, it was found that Japanese women college students consumed many kinds of food, and therefore, their vitamin nutrition was good as compared to the RDA values for level III of physical activity; however, their energy intake (1,622+/-377 kcal) was lower than the RDA for level III (2,050 kcal/d). Their strength of physical activity would be level I. Therefore, in consideration of their lifestyle, their energy intakes is considered adequate. In conclusion, a problem for student lifestyle is a shortage of food intake due to lack of exercise.     

Fat-soluble and water-soluble vitamin contents of breast milk from Japanese women

To determine the concentrations of fat-soluble and water-soluble vitamins in the maternal milk of Japanese women, we collected human milk samples from more than 4,000 mothers living throughout Japan between December 1998 and September 1999, and defined as group A the 691 samples among these that met the following conditions: breast milk of mothers who were under 40 y of age, who did not smoke habitually and/or use vitamin supplements, and whose babies showed no symptoms of atopy and had birth weights of 2.5 kg or more. We then analyzed the contents of vitamins individually. Large differences were observed among the contents of individual human milk samples. The mean contents of each component were as follows: vitamin A, 159.0 +/- 95.2 IU/100 mL; vitamin E, 0.325 +/- 0.165 alpha-TE mg/100mL; vitamin D3 (cholecalciferol), 8.0 +/- 10.7 ng/100mL; vitamin B1 (thiamin), 12.3 +/- 3.2 microg/100 mL; vitamin B2, 38.4 +/- 12.7 microg/100 mL; vitamin B6, 5.7 +/- 2.5 microg/100 mL; vitamin B12, 0.04 +/- 0.02 microg/100 mL; vitamin C, 5.1 +/- 1.9 mg/100 mL; biotin, 0.50 +/- 0.23 microg/100 mL; choline, 9.2 +/- 1.8 mg/100 mL; folic acid, 6.2 +/- 2.9 microg/100 mL; inositol, 12.6 +/- 3.6 mg/100 mL; niacin (nicotinamide), 32.9 +/- 20.4 microg/100 mL and pantothenic acid, 0.27 +/- 0.09 mg/100 mL. The concentrations of derivatives and/or related compounds of vitamin A (retinol, beta-carotene), vitamin E (alpha-, beta-, gamma-, and delta-tocopherol), and B2 (riboflavin, FMN, and FAD) were determined separately. The contents of each were found to vary greatly as the duration of lactation increased. The present results indicate that it is necessary to evaluate individual differences in human milk in order to perform valid research regarding infant formula.     

Effect of fortified spread on homocysteine concentration in apparently healthy volunteers

OBJECTIVE: To determine the effect of folic acid, vitamin B(6) and B(12) fortified spreads on the blood concentrations of these vitamins and homocysteine. DESIGN AND SETTING: A 6-week randomized, double-blinded, placebo-controlled, parallel trial carried out in a clinical research center. SUBJECTS: One hundred and fifty healthy volunteers (50% males). INTERVENTIONS: For 6 weeks, the subjects consumed the test spreads (20 g/day): containing per 20 g (1) 200 microg folic acid, 2 microg vitamin B(12) and 1 mg vitamin B(6), or (2) 400 microg folic acid, 2 microg vitamin B(12) and 1 mg vitamin B(6) or (3) no B-vitamins (control spread). RESULTS: The B-vitamin status increased on using the test spreads, with the largest effect on the serum folate concentration: 48% in men and 58% in women on spread 1 and 92 and 146%, respectively, on spread 2 (P-values all <0.05). The plasma homocysteine decreased in the groups treated with the fortified spreads as compared to the control group. Average decreases were for males: 0.7+/-1.5 micromol/l (6.8%) on spread 1 and 1.7+/-1.7 micromol/l (17.6%) on spread 2 and for females: 1.4+/-1.2 micromol/l (14.2%) and 2.4+/-2.0 micromol/l (23.3%), respectively (P-values all <0.05). CONCLUSIONS: Consumption of a spread fortified with folic acid, vitamin B(6) and vitamin B(12) for 6 weeks significantly increases the blood concentrations of these vitamins and significantly decreases the plasma concentration of homocysteine. Fortified staple foods like spreads can contribute to the lowering of homocysteine concentrations.     

Retinoic acid metabolites in plasma are higher after intake of liver paste compared with a vitamin A supplement in women.

The objectives of the present study were to compare the bioavailability of vitamin A from liver paste and from a vitamin A supplement at three nutritionally relevant levels of intake, and to estimate levels of "safe" intake based on concentrations of retinoic acid and its metabolites in plasma after a single dose of vitamin A from liver paste. Women (n = 35; 19-47 y of age) consumed 3.0, 7.5 or 15 mg vitamin A as liver paste or as a vitamin A supplement with a test meal in a randomized design, with a combined crossover (two sources) and parallel approach (three dosages). Retinyl esters and retinoic acid (RA) metabolites were quantified in blood samples at 2-24 h after dosing. The areas under the time-response curves (AUC) were calculated to evaluate responses in plasma vitamin A after intake of liver paste and the vitamin A supplements. For retinyl esters, the AUC was significantly affected by the dosage, but not by the source. The formation of 13-cis-RA, 13-cis-4-oxo-RA, and to a lesser extent all-trans-RA was significantly higher after consumption of liver paste compared with the supplement, especially at higher dosages. Long-term baseline concentrations of retinol were not affected by a single intake of vitamin A. In conclusion, the bioavailability of vitamin A from single doses of liver paste and a vitamin A supplement does not differ, but the plasma concentrations of RA metabolites are higher after intake of liver paste. Thus, pregnant women should indeed limit the intake of vitamin A from liver products.     

Protective effect of soybean saponins and major antioxidants against aflatoxin B1-induced mutagenicity and DNA-adduct formation

Saponins from various plant sources have been suggested as possible anticarcinogens. Major dietary sources of saponins include legumes such as soybeans. This study was performed to determine the effect of soybean saponins on aflatoxin B(1)(AFB(1))-induced mutagenicity and AFB(1)-DNA adduct formation using Salmonella typhimurium and human liver hepatoma (HepG2) cells, respectively. Major antioxidants including L-ascorbic acid, alpha-tocopherol, all-trans-retinol, and butylated hydroxytoluene (BHT), previously reported to possess antimutagenic activity, were used as test materials to evaluate the relative effectiveness of saponins. Results indicated antimutagenicity was in the order of BHT > saponins > alpha-tocopherol > L-ascorbic acid. Soybean saponins exerted a significant effect, inhibiting the mutagenicity of AFB(1) by 52%, 64%, and 81% at concentrations of 600, 900, and 1,200 microg per plate, respectively. The amount of tritiated AFB(1) metabolites-DNA adducts formed in HepG2 cells was significantly reduced when cells were preincubated with 10 or 30 microg/ml of test materials. Soybean saponins inhibited AFB(1)-DNA adduct formation by 50.1% at a concentration of 30 microg/ml, whereas L-ascorbic acid and BHT reduced adduct formation by 38.4% and 32.6%, respectively, at the same concentrations. These results indicate that soybean saponins possess not only a significant antimutagenic activity but a strong inhibitory action against carcinogen-induced DNA damages. Soybean saponins possibly block the initiation stage of carcinogenesis, and further studies are required to elucidate the mechanisms of action.     

Breakfast cereal fortified with folic acid, vitamin B-6, and vitamin B-12 increases vitamin concentrations and reduces homocysteine concentrations: a randomized trial

BACKGROUND: High homocysteine and low B vitamin 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, vitamin B-6, and vitamin B-12 on vitamin 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 vitamin supplements or highly fortified breakfast cereal. Subjects were randomly assigned to consume 1 cup (0.24 L) breakfast cereal fortified with 440 microg folic acid, 1.8 mg vitamin B-6, and 4.8 microg vitamin B-12 or placebo cereal for 12 wk. Blood was drawn at 0, 2, 12, and 14 wk. Methionine-loading tests were conducted at baseline and week 14. RESULTS: Final baseline-adjusted plasma homocysteine concentrations were significantly lower and B vitamin 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 vitamin B-12 concentrations < 185 pmol/L from 9% to 3%, with vitamin B-6 concentrations < 20 nmol/L from 6% to 2%, and with homocysteine concentrations > 10.4 micromol/L (women) or > 11.4 micromol/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 vitamin and decreased homocysteine concentrations, including post-methionine-load homocysteine concentrations.     

Underutilised legumes: potential sources for low-cost protein

Seeds of 104 leguminous species belonging to 17 genera were analysed for their protein contents. The promising ones were investigated for fibre, carbohydrate, ash, oil, fatty acids, amino acid profile and trypsin inhibitor activity (TIA). The variation of fibre contents was 4.1-8.9%, carbohydrate 18.4-49.2%, ash 1.8-7.2%, TIA 48.7-87.5 mg/g, oil 1.3-19.8% and protein 11.0-51.6%. The protein content (41-45%) in Acacia mellifera (41.6%), Albizzia lebbek (43.6%), Bauhinia triandra (42.7%), Lathyrus odoratus (42.8%), Parkinsonia aculeata (41.6%), Psophocarpus tetragonolobus (41.9%), Sesbania paludosa (41.2%) and S. sesban (43.8%) was in close proximity to soybean (42.8%), whereas Bauhinia retusa (51.6%), B. variegata (46.5%), Delonix elata (48.7%) and Gliricidia maculata (46.3%) showed higher percentages of protein than soybean. The essential amino acid composition of some of the seed proteins was reasonably well balanced (lysine up to 7.6%). The seeds of Bauhinia retusa (18.6%), B. triandra (16.5%), B. variegata (17.3%), Gliricidia maculata (16.2%), Parkia biglandulosa (18.9%) and Psophocarpus tetragonolobus (19.8%) had a good amount of oil, comparable to soybean (18-22%). The fatty acid composition of some genera/species was quite promising with high amount of unsaturated fatty acids.     

Effects of maternal micronutrient supplementation on fetal loss and infant mortality: a cluster-randomized trial in Nepal

BACKGROUND: We previously reported that maternal micronutrient supplementation in rural Nepal decreased low birth weight by approximately 15%. OBJECTIVE: We examined the effect of daily maternal micronutrient supplementation on fetal loss and infant mortality. DESIGN: The study was a double-blind, cluster-randomized, controlled trial among 4926 pregnant women and their 4130 infants in rural Nepal. In addition to vitamin A (1000 microg retinol equivalents), the intervention groups received either folic acid (FA; 400 microg), FA + iron (60 mg), FA + iron + zinc (30 mg), or multiple micronutrients (MNs; the foregoing plus 10 microg vitamin D, 10 mg vitamin E, 1.6 mg thiamine, 1.8 mg riboflavin, 2.2 mg vitamin B-6, 2.6 microg vitamin B-12, 100 mg vitamin C, 64 microg vitamin K, 20 mg niacin, 2 mg Cu, and 100 mg Mg). The control group received vitamin A only. RESULTS: None of the supplements reduced fetal loss. Compared with control infants, infants whose mothers received FA alone or with iron or iron + zinc had a consistent pattern of 15-20% lower 3-mo mortality; this pattern was not observed with MNs. The effect on mortality was restricted to preterm infants, among whom the relative risks (RRs) were 0.36 (95% CI: 0.18, 0.75) for FA, 0.53 (0.30, 0.92) for FA + iron, 0.77 (0.45, 1.32) for FA + iron + zinc, and 0.70 (0.41, 1.17) for MNs. Among term infants, the RR for mortality was close to 1 for all supplements except MNs (RR: 1.74; 95% CI: 1.00, 3.04). CONCLUSIONS: Maternal micronutrient supplementation failed to reduce overall fetal loss or early infant mortality. Among preterm infants, FA alone or with iron reduced mortality in the first 3 mo of life. MNs may increase mortality risk among term infants, but this effect needs further evaluation.     

A preliminary open label dose comparison using an antioxidant regimen to determine the effect on viral load and oxidative stress in men with HIV/AIDS

OBJECTIVE: To investigate the effect of antioxidant supplementation on viral load and the antioxidant/reactive oxygen species system in people with HIV. DESIGN: Single centre, prospective, dose comparison study. SETTING: Outpatient clinic specializing in HIV care. SUBJECTS: Sixty-six participants were sequentially recruited by advertisement, and 48 subjects completed the study. INTERVENTIONS: A recommended dose antioxidant regimen (5,450 IU vitamin A as beta-carotene, 250 mg vitamin C, 100 IU vitamin E, 100 microg selenium, 50 mg coenzyme Q10) or a high-dose antioxidant regimen (21,800 IU vitamin A as beta-carotene, 1,000 mg vitamin C, 400 IU vitamin E, 200 microg selenium, 200 mg coenzyme Q10) for a 12 week period. RESULTS: Using repeated measures analysis of variance, the changes over treatment time were significant for selenium, glutathione, glutathione peroxidase and lipid peroxides (P < 0.03). Changes in allantoin, uric acid and viral load were not significant (P > 0.05). The main effects for group and the interaction effects were not significant for any of the parameters measured (P > or = 0.05). CONCLUSION: Antioxidant supplementation significantly improved some measures of oxidative defence. There was no benefit in using a high-dose supplement in this study.     

Amino acid profiles of sufu, a Chinese fermented soybean food

Sufu is a Chinese soybean cheese-like product obtained by solid-state fungal fermentation and ripening of tofu. The resulting “pehtze” is salted, followed by maturation in brine. Total (TAA) and free amino acid (FAA) profiles were determined during consecutive stages of sufu manufacture, i.e., tofu, pehzte (fungal fermented tofu), salted pehtze and in white, red and grey sufu, ripening in dressing mixtures of different salt content (8%, 11%, and 14% w/w). TAA in tofu, pehtze and salted pehtze totalled 547, 551 and 351 mg/g dry matter, respectively. FAA increased from total 1.3 to 15.6 mg/g dm in pehtze after fermentation of tofu by Actinomucor elegans and to 11.9 mg/g dm in salted pehtze. During ripening up to 80 days, total FAA in red sufu increased from 28 to 88 mg/g (8% salt), 28–63 mg/g (11% salt) or 26–42 mg/g (14% salt). In white sufu the levels of FAA were generally higher and the effect of salt was less inhibitory. Levels of FAA in white sufu increased in 80 days from 33 to 104 mg/g (8% salt), 27–92 mg/g (11% salt) and 19–73 mg/g (14% salt). The pattern of essential amino acids compared favourably with those of eggs and cow's milk. While FAA increased during ripening of red and white sufu, the ratio of each amino acid remained essentially constant, and glutamic acid, leucine, aspartic acid, alanine, phenylalanine and lysine were found in large quantities. However, in grey sufu the ratio was different, with large proportions of leucine, alanine, isoleucine, valine and phenylalanine found after ripening.     

Japanese soybean paste miso scavenges free radicals and inhibits lipid peroxidation.

Japanese soybean paste miso, which has been reported to prevent gastric and mammary cancer and chronic nephritis, was demonstrated by electron spin resonance spectrometry using 5,5'-dimethyl-1-pyrroline-N-oxide as a scavenger of free radicals. Fifty mg/ml of miso scavenged 100% of 1,1-diphenyl-2-picrylhydrazyl radicals (3.9 x 10(15) spins/ml); 45 mg/ml quenched 92% of hydroxyl radicals (7.9 x 10(16) spins/ml); and 50 mg/ml quenched 50% of superoxide anion (6.7 x 10(16) spins/ml). In the system of rat cerebral cortex homogenate supplemented with 2 mM each of Fe2+ and ascorbic acid, 90% and 82% of the hydrogen and carbon-centered radicals having 1.7 x 10(13) spins/ml and 3.9 x 10(13) spins/ml, respectively, were quenched by 180 mg/ml of miso. The thiobarbituric acid-reactive substances, an index of lipid peroxidation in the brain, was inhibited by 10 mg/ml of miso. These results showed that miso acts as an antioxidant by scavenging free radicals.     

Inhalable dust and protein exposure in soybean processing plants

Little is known about inhalable dust concentrations in soybean processing plants in southern Africa. This project measured inhalable dust in soybean plants in the region and correlated dust measurements with total protein and soy trypsin inhibitor. Sixty-four personal inhalable dust measurements were taken in three processing plants. Levels of total protein and soy trypsin inhibitor were determined in only two of the three plants. Correlations between inhalable dust, total protein and trypsin inhibitor were determined for 44 of 64 samples. In plants' production areas, inhalable dust levels were 0.24-35.02 mg/m3 (median 2.58 mg/m3). Total protein and soy trypsin inhibitor levels were 29.41-448.82 microg/m3 (median 90.09 microg/m3) and 0.05-2.58 microg/m3 (median 0.07 microg/m3), respectively. No statistically significant correlations between presence of inhalable dust and soy trypsin inhibitor were found. Total protein and soy trypsin inhibitor were better correlated. This study indicates that total protein might be a good proxy for soybean specific protein concentrations in soybean processing plants.     

Palm and partially hydrogenated soybean oils adversely alter lipoprotein profiles compared with soybean and canola oils in moderately hyperlipidemic subjects

BACKGROUND: Partially hydrogenated fat has an unfavorable effect on cardiovascular disease risk. Palm oil is a potential substitute because of favorable physical characteristics. OBJECTIVE: We assessed the effect of palm oil on lipoprotein profiles compared with the effects of both partially hydrogenated fat and oils high in monounsaturated or polyunsaturated fatty acids. DESIGN: Fifteen volunteers aged > or =50 y with LDL cholesterol > or =130 mg/dL were provided with food for each of 4 diets (35 d/phase) varying in type of fat (partially hydrogenated soybean, soybean, palm, or canola; two-thirds fat, 20% of energy). Plasma fatty acid profiles, lipids, lipoproteins, apolipoprotein A-I, apolipoprotein B, lipoprotein(a), glucose, insulin, HDL subfractions, and indicators of lipoprotein metabolism (HDL-cholesterol fractional esterification rate, cholesteryl ester transfer protein, phospholipid transfer protein, and paraoxonase activities) were measured at the end of each phase. RESULTS: Plasma fatty acid profiles reflected the main source of dietary fat. Partially hydrogenated soybean and palm oils resulted in higher LDL-cholesterol concentrations than did soybean (12% and 14%, respectively; P < 0.05) and canola (16% and 18%; P < 0.05) oils. Apolipoprotein B (P < 0.05) and A-I (P < 0.05) concentrations mirrored the pattern of LDL- and HDL-cholesterol concentrations, respectively. No significant effect on the total-to-HDL cholesterol ratio was observed for palm oil compared with the other dietary fats. HDL3 cholesterol was higher after palm oil than after partially hydrogenated and soybean oils (P < 0.05). Differences in measures of glucose and HDL intravascular processing attributable to dietary fat were small. CONCLUSION: Palm and partially hydrogenated soybean oils, compared with soybean and canola oils, adversely altered the lipoprotein profile in moderately hyperlipidemic subjects without significantly affecting HDL intravascular processing markers.     

The coexistence of other micronutrient deficiencies in anaemic adolescent schoolgirls in rural Bangladesh

OBJECTIVE: To investigate the prevalence of selected micronutrient deficiencies amongst anaemic adolescent schoolgirls in rural Bangladesh and to examine their relationship with haemoglobin (Hb) levels. DESIGN: A cross-sectional study. SETTING: Girls' high schools in rural areas of Dhaka District in Bangladesh. SUBJECTS AND METHODS: Three hundred and ten anaemic adolescent girls aged 14-18 years from eight schools participated in the study. Information on personal characteristics and food habits were collected by interview. Parents were asked about their socio-economic conditions. Anthropometric data and blood samples were collected following the interview. RESULTS: Twenty-eight per cent of the girls had depleted iron stores (serum ferritin <12.0 microg/l), 25% had folic acid deficiency (red blood cell folic acid <317 nmol/l), 89% had vitamin B(2) (erythrocyte glutathione reductase activity coefficient > or =1.4) and 7% had vitamin B(12) deficiencies (serum vitamin B(12) <150 pmol/l). Although the prevalence of vitamins A and C deficiency was very low, a significant proportion had low vitamin A (serum retinol between 0.70 and <1.05 micromol/l) and vitamin C status (plasma ascorbic acid between 11.4-23.0 micromol/l). Frequency of consumption of meat, serum ferritin and vitamin B(2) status were found to be strongly related to Hb by multiple regression analysis. For 1 microg/l change in serum ferritin, there was a 0.13 g/l change in Hb when adjusted for other factors. CONCLUSIONS: There is coexistence of micronutrient deficiencies among anaemic adolescent girls in rural Bangladesh, although they do not suffer from energy deficiency. Of all micronutrients, only iron and vitamin B(2) concentrations were found to be related to the Hb concentration.     

Effect of B vitamins-fortified foods on primary school children in Beijing

The objective of this study is to investigate the effect of B vitamins-fortified foods on primary school children. A controlled trial was conducted in 101 normal primary school children aged 9-11 years. They were randomly assigned to supplemental control group (S-control, n=36), riboflavin supplementation group (+riboflavin 0.625 mg/day, n=32), and B vitamin compound supplementation group (+riboflavin 0.625 mg/day, +thiamin 0.512 mg/day, +nicotinic acid 0.365 mg/day, +folic acid 0.13 mg/day, n=33) based on school classes. Urinary riboflavin excretion and erythrocyte glutathione reductase activity coefficient (EGRAC) along with erythrocyte transketolase activity (ETKA) were used to evaluate B vitamin levels in the children. AYP index, an index reflecting the brain performance ability, was chosen to assess the children's study abilities. Health education was carried out to help children and their parents adopt scientific dietary concepts. The urinary riboflavin excretion was higher in two supplementation groups (435.24 +/- 153.3 microg/g creatinine, 374.6 +/- 144.6 microg/g creatinine) than in S-control group (235.1 +/- 86.2 microg/g creatinine). Average values of EGRAC were lower in two supplementation groups (0.90 +/- 0.11, 0.80 +/- 0.10) than in S-control group (1.08 +/- 0.25). At the same time, the percentage of thiamine pyrophosphate (TPP%) decreased from 63.69 +/- 28.04 to 42.16 +/- 16.31 in B vitamin compound supplementation group. Meanwhile, AYP index increased at the end of the supplementation in two supplementation groups. B vitamins supplementation can significantly increase B vitamin level in children. Biochemical activities of riboflavin and thiamin can improve with the intake of fortified foods. The effect of B vitamin compound supplementation is better than that of single riboflavin supplementation when the effect of riboflavin's biofunction is considered. In addition, micronutrient supplementation appears to assist children's study abilities.     

Dietary casein and soybean protein affect the concentrations of serum cholesterol, triglyceride and free amino acids in rats.

This work was undertaken to investigate the concentrations of free amino acids in blood after food was withheld from growing, male Wistar rats fed cholesterol-free, low fat (1 g corn oil/100 g) diets with casein or soybean protein for 2 wk. A diet containing 22.5 or 23.5 g/100 g of soybean protein was hypocholesterolemic compared with a diet containing 20.0 g casein/100 g diet. A comparison of serum amino acids in soybean protein-fed vs. casein-fed rats showed that, whereas concentrations of many amino acids were lower in the soybean protein-fed rats compared with the casein-fed groups, glycine was the only amino acid having a higher concentration. Further, alanine was significantly lower in the soybean protein-fed rats compared with the casein-fed rats, and the protein-induced differences in glycine and alanine concentrations of unfed rats were reproducible. When diets containing 15.0% casein or 30.0% soybean protein, a casein diet supplemented with glycine and a soybean protein diet supplemented with methionine were compared, the changes in serum glycine and alanine correlated with the changes in serum cholesterol. Concentrations of several amino acids, particularly valine, leucine and tyrosine, also changed when serum cholesterol concentrations varied, but these effects could not be explained by our experiments. The results suggest that a change in serum concentration of glycine and alanine of unfed rats may be related to the change in serum cholesterol concentration.     

Testicular injury to rats fed on soybean protein-based vitamin B12-deficient diet can be reduced by methionine supplementation

We have previously reported that rats fed on a vitamin B12 (B12)-deficient diet containing 180 g soybean protein per kg diet showed marked histologic damage in their testes. In this paper, we report the effect of B12-deficiency on B12-dependent methionine synthase in the rats' testes and the effect of methionine supplementation of the diet on testicular damage. Rats were fed the soybean protein-based B12-deficient diet for 120 d. We confirmed that those rats were in serious B12-deficiency by measuring urinary methylmalonic acid excretion and B12 content in tissues. Methionine synthase activity in the testis of the B12-deficient rats was less than 2% of that in B12-supplemented (control) rats. To complement disrupted methionine biosynthesis, methionine was supplied in the diet. A supplement of 5 g D,L-methionine per kg diet to the B12-deficient diet did not affect urinary methylmalonic acid excretion of B12-deficient rats. The testicular histology of rats fed the methionine-supplemented B12-deficient diet was almost indistinguishable from that of control rats. Thus, we conclude that the lowered testicular methionine synthase activity is the primary cause of the histologic damage due to B12-deficiency and that methionine supplementation to the diet can reduce the damage. These findings would indicate the importance of the methionine synthase activity, especially for testicular function.     

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).     

The multiple vitamin status of Chinese pregnant women with anemia and nonanemia in the last trimester

Iron-deficiency or anemia in pregnancy is a major public health problem in China. This cross-sectional study was carried out to observe the association between iron status and multiple vitamin levels of Chinese pregnant women in the third trimester. We measured iron, ascorbic acid, retinol, folate and vitamin B12 in serum, and riboflavin in urine specimens of 1,163 pregnant women in four sites throughout rural and city areas in China. Based on hemoglobin concentrations (Hb), the subjects were divided into an anemia group with Hb < 110 g/L or Hb < or = 100 g/L as severe anemia group, and nonanemia group with Hb > or = 110 g/L. Results showed that 41.58% of the population with serum iron < 700 microg/L and 51.04% of the population with ferritin < 12 microg/L in the anemia group, percentages that were much higher than those in the nonanemia group. Relationships between five vitamins and hemoglobin concentrations of all subjects were observed. There was a lower level of serum ascorbic acid (291.05 microg/dL) in the Hb < or = 100 g/L group than in the Hb > or = 120 g/L group (487.79 microg/dL) (p < 0.001). Serum levels of vitamin B12 and folate were 445.67 pg/mL and 5.94 ng/mL in the Hb < or = 100 g/L group, whose levels were much lower than the levels of 502.01 pg/mL (p < 0.012) and 8.07 ng/mL (p < 0.010) respectively in the Hb > or = 120 g/L group. Further, cross-sectional analysis showed positive correlations between abnormal hematological results and prevalences of vitamin deficiencies. The subjects with iron-deficiency anemia had much higher rates of vitamin C, folate and vitamin B12 deficiencies than those in the nonanemic subjects, and especially in the deficient rates of ascorbic acid and folate in the anemia (Hb < 110 g/L) group, which reached 64.04% and 22.70% respectively. Moreover, we observed that the decreasing trends of hemoglobin concentrations were accompanied by the decreases of serum levels of vitamin A, ascorbic acid, folate and vitamin B12. In conclusion, multiple vitamin deficiencies, especially ascorbic acid, retinol and folic acid, may be associated with anemia or iron deficiency in pregnant women in the last trimester. The study suggested that anemic pregnant women in China should be supplemented with iron and multiple vitamins simultaneously.