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PubMed2002

[Beliefs on vitamin and consumption of vitamin supplements among university students in the city of São Paulo].

A survey was conducted in a sample of 894 students entering a private university in São Paulo to examine the vitamin beliefs and to verify the relation between vitamin beliefs and vitamin supplements consumption. Nineteen statements about the relation between vitamins and health were developed to assess the beliefs; the respondents answered by means of a 5-point agreement scale. Cronbach's alpha coefficient of internal consistency was determined for the total scale. 94.5% of students believe that vitamin C prevents and cures the common cold and 72.5% consider vitamins as an energy source. Many students recognize the possibility of health risks associated to excessive vitamin consumption. Vitamin supplement users had a belief score higher than non-users (p < 0.001). The results indicate that several misconceptions about vitamin benefits are common among the students and suggest a relation between vitamin beliefs and supplements consumption.

Adolescent↗
PubMed1976

Synthesis of 1alpha-hydroxy [6-3H]vitamin D3 and its metabolism to 1alpha, 25-dihydroxy [6-3H]vitamin D3 in the rat.

1alpha-Hydroxy [6-3H]vitamin D3 has been synthesized with a specific activity of 4 Ci/mmol, and its metabolism in rats has been studied. It is rapidly converted to 1alpha,25-dihydroxy [6-3H]vitamin D3 in vivo. Following an intravenous or oral dose, a maximal concentration of 1alpha,25-dihydroxy [6-3H]vitamin D3 is found 2 and 4 hours, respectively, before the maximal intestinal calcium transport response is observed. Similarly, 1alpha,25-dihydroxy[6-3H]vitamin D3 accumulation in bone precedes the bone calcium mobilization response. It appears, therefore, that the biological activity of 1alpha-hydroxyvitamin D3 is largely, if not exclusively, due to its conversion to 1alpha,25-dihydroxy[6-3H]vitamin D3 1alpha-Hydroxy[6-3H]vitamin D3 and 1alpha,25-dihydroxy[6-3H]vitamin D3 appear in intestine equally well after an oral or an intravenous dose of 1alpha-hydroxy[6-3H]vitamin D3. However, much less of both 1alpha-hydroxy[6-3H]vitamin D3 and 1alpha,25-dihydroxy[6-3H]vitamin D3 appears in bone and blood after an oral than after an intravenous dose. A much reduced bone calcium mobilization response is also noted following an oral dose as compared to an intravenous dose of 1alpha-hydroxyvitamin D3, suggesting that oral 1alpha-hydroxyvitamin D3 is not utilized as well as intravenously administered material.

Animals↗
PubMed2004

Lowered plasma vitamin C, but not vitamin E, concentrations in dementia patients.

BACKGROUND: Alzheimer s disease (AD), according to the free radical hypothesis, affects brain regions where free radical damage occurs. Antioxidant nutrients may help to protect these brain regions. OBJECTIVE: To investigate whether plasma vitamin C and E status is lowered in subjects with AD and dementia. DESIGN: A case control study was conducted in 93 institutionalized subjects aged 65 + yrs. The dementia group (N = 43) included 15 subjects with Alzheimer s Disease (AD) and 28 subjects with senile dementia, while the control group included 50 subjects with no cognitive impairment. Subjects with uncontrolled hypertension and/or diabetes were excluded from the study. Plasma vitamin C and E was determined using the 2,6- dichlorophenolindophenol and the HPLC methods, respectively. Dietary intake, including dietary supplements, was assessed using a 2-day plate-waste method. Cognitive function was measured using the MMSE and nutritional status assessed using the Mini Nutritional Assessment (MNA) tool. RESULTS: The control group had significantly higher scores for the MNA, MMSE and Activities of Daily Living, compared with the dementia group. Controls had a significantly higher plasma vitamin C concentration than dementia patients (median = 0.84 (IQR = 0.54) mg/dl and 0.56 (0.80) mg/dl, respectively; P<0.05). The dementia group were more likely to have sub-optimal plasma vitamin C levels (< 0.6 mg/dl) than control subjects (OR = 2.99; 95 % CI = 0.95 9.79; P<0.05), despite having similar dietary vitamin C intakes. Plasma vitamin C was positively associated with MMSE score (r = 0.21; P<0.05). No difference was found between the groups for either plasma or dietary vitamin E. CONCLUSION: Plasma vitamin C levels were lower in subjects with dementia compared to controls, which was not explained by their dietary vitamin C intakes. This data supports the free radical theory of oxidative neuronal damage. Further investigations of whether supplementation with this vitamin may prevent or delay the progression of cognitive decline in patients with AD and senile dementia appear warranted.

Activities of Daily Living↗
PubMed2004

[The effect of vitamin-mineral supplementation on vitamins D, A (beta-carotene) and E concentration in blood of matched maternal-cord pairs].

The aim of the present study was to investigate the effect of Vibovitmama supplementation on status of fat soluble vitamins D, A (beta-carotene) and E in blood of pregnant women and in umbilical cord blood of their children. In group taking Vibovitmama serum concentration of vitamin D, was higher by 10% than in the placebo group was observed. However it was within the normal range and was not statistically significant. Supplementation affected vitamin D concentration in serum of cord blood. It was higher by 20% in the group taking vitamin preparation than in group taking placebo and was statistically significant (p < 0.05). Retinol and beta-carotene in plasma increased during pregnancy by 15% and 25% (p < 0.002) respectively in placebo and supplemented group. In umbilical cord blood in the group taking Vibovitmama, concentration of vitamin A was 1.52 micromol/L and of beta-carotene 1.86 micromol/L versus 1.45 micromol/L and 1.79 micro/L found in group of placebo. In plasma level, vitamin E was higher in late pregnancy than in the I trimester (by about 40%) and was not modified by vitamins supplementation. In erythrocytes the concentration of tocopherol increased by 18% in placebo and by 25% in group taking Vibovitmama. In the plasma of cord blood level of vitamin E was not modified by supplementation, whereas in red blood cells it was slightly increased (by 10%) but not statistically significant. Our results suggest that vitamin-mineral supplementation of pregnant women improved status of fat soluble vitamins in mothers and their children.

Adult↗
PubMedDate not supplied

Association between breast cancer and vitamin C, vitamin E and selenium levels: results of a case-control study in India.

In women, cancer of the breast is generally the most prevalent neoplasm and cause of cancer death. Though a large number of women are affected with breast cancer, very few studies have been undertaken in India on the association between micronutrients and the risk of breast cancer. We conducted a hospital based case- control study to examine the associations of vitamin C, vitamin E and selenium with breast cancer. One hundred and sixty breast cancer patients and an equal number of normal healthy individuals constituted the study population. Venous blood was collected from the cases and controls for estimation of vitamin C, vitamin E and selenium utilizing standard procedures. Univariate logistic regression analysis was carried out to calculate odds ratios and confidence intervals. The mean vitamin C, vitamin E and selenium levels were lower in patients as compared to the controls. There was a 84% and 77% lower risk of breast cancer if the levels of vitamin C and vitamin E were increased by 1 unit, respectively. Similarly, there was a 7% lower risk of breast cancer if the level of selenium was increased by 1 unit. The results of the present study thus indicated a strong association of vitamin C, vitamin E and selenium with breast cancer in the Indian population.

Adult↗
PubMed1982

Analysis of fat-soluble vitamins. XXVI. High performance liquid chromatographic determination of vitamin D in fortified milk and milk powder.

Vitamin D is determined by high performance liquid chromatography (HPLC) in samples containing other fat-soluble vitamins. The vitamin D in the unsaponifiable residue is extracted and separated from interferences by straight phase chromatography, and the fraction corresponding to vitamin D3 is collected and quantitated using the AOAC official final action HPLC method for vitamin D3. Analysis of a synthetic mixture gave reasonable recoveries. The method measures potential vitamin D3 content in milkpowder samples containing 2 IU vitamin D/g in the presence of all known vitamin D3 isomers, vitamin A, and vitamin E.

Animals↗
PubMed1995

Breast-milk vitamin A as an indicator of the vitamin A status of women and infants.

This article reviews the evidence for using breast-milk vitamin A as an indicator of vitamin A status and provides technical information for researchers who want to use this indicator to assess the vitamin A status of women and breast-fed children. Breast-milk vitamin A is a unique indicator for assessing the vitamin A status of lactating women and their breast-fed infants, and has recently been recommended by WHO for use in monitoring global elimination of vitamin A deficiency. Assessing breast-milk vitamin A is less invasive than alternative approaches for assessing a mother's vitamin A status and not at all invasive for her infant. Collection of milk samples in the field is generally feasible and acceptable. Breast-milk vitamin A appears to be an especially good indicator for measuring the impact of vitamin A interventions on women and infants, and for this purpose, it is more responsive than other indicators.

Feasibility Studies↗
PubMedDate not supplied

[Comparison of metabolism of water-soluble vitamins in healthy children and in children with insulin-dependent diabetes mellitus depending upon the level of vitamins in the diet].

Metabolism of vitamins C, B2, B6 and niacin in children with insulin-dependent diabetes mellitus was distinctly different from that of healthy persons of the same age as shown by studies of the correlation between content of vitamins or their coenzyme forms in blood, excretion of the vitamins with urine and content of the vitamins in a diet. These data corroborated once again that in estimation of the vitamins consumption suitable for ill children, the criteria of healthy children requirements for vitamins should not be taken into consideration. Dissimilar metabolism in healthy and impaired persons may also demonstrate some differences in consumption of these vitamins. Preliminary data showed that requirements of the impaired children for vitamin C were slightly increased, for vitamin B2--similar or slightly decreased as compared with healthy children. These results suggest that additional investigations are required for evaluation of vitamins consumption in children with diabetes mellitus of the I type.

Adolescent↗
PubMed1997

Effects of water supplementation with selenium and vitamin E on growth performance and blood selenium and serum vitamin E concentrations in weanling pigs.

OBJECTIVE: To determine effects of supplementation of drinking water with selenium and vitamin E on blood selenium and serum vitamin E concentrations, growth performance, and water intake of pigs. DESIGN: Prospective controlled study. ANIMALS: 228 weanling pigs. PROCEDURE: In experiments 1 and 2, pigs were given drinking water supplemented with selenium and vitamin E, and blood selenium and serum vitamin E concentrations were measured. In experiment 3, growth performance and water intake were measured in pigs that received supplemented water for 2 or 5 weeks and in control pigs. RESULTS: In experiment 1, blood selenium concentrations were significantly increased after 7 days of supplementation, and serum vitamin E concentrations were significantly increased after 1 and 7 days of supplementation, compared with baseline concentrations. In experiment 2, blood selenium concentrations were not significantly different between treated and control pigs, and serum vitamin E concentrations were significantly increased on day 7. In experiment 3, gain-to-feed ratios were significantly higher for pigs supplemented with selenium and vitamin E for 5 weeks, but other differences were not detected. CLINICAL IMPLICATIONS: Supplementation of drinking water with selenium and vitamin E may improve the selenium and vitamin E status of weanling pigs by increasing selenium and vitamin E intake.

Analysis of Variance↗
PubMed1998

A short-term supplementation of pregnant women before delivery does not improve significantly the vitamin E status of neonates--low efficiency of the vitamin E placental transfer.

Little is known about lipid-soluble vitamin placental transfer. We supplemented ten pregnant women ranging in age from 26 to 38 years with vitamin E at a daily dose of 1 g dl-alpha-tocopherol acetate for 3 days before delivery. All pregnancies ranged from 37 to 39 weeks of gestation at the time of the study. Maternal blood was first drawn during the week preceding supplementation and then just before the delivery by hysterotomy. Neonatal blood was from cord at birth. Supplementation dramatically increased the plasma and red blood cell vitamin E of the mothers. This was true whatever the expression of the vitamin E content, i.e., plasma lipid-normalized or non-normalized vitamin E, and red blood cell vitamin E related to volume of packed cells or to membrane-phospholipid phosphorus. In contrast, the plasma vitamin E content was very low in neonates (3.51 +/- 0.38 mg/L) and did not significantly differ from that reported in a previous paper, where plasma was drawn from fetal cord blood of pregnant non-supplemented women belonging to the same geographical population (Cachia et al., Am. J. Obstet. Gynecol. 1995; 173: 42-51). This strongly suggests that the transfer of vitamin E through the placental barrier is very low. That the plasma lipid-normalized levels of mothers before supplementation and of neonates did not significantly differ also suggests that the paucity of lipids in the circulating blood of neonates is the cause of the restricted amount of plasma vitamin E. Therefore, the low level of vitamin E in neonates may result from both low maternal placental transfer and neonatal lipid transport peculiarities.

Administration, Oral↗
PubMed1989

Vitamin K absorption capacity and its association with vitamin K deficiency.

We measured plasma vitamin K concentrations in 194 5-day-old infants three hours after administration of a 4-mg dose of vitamin K (menaquinone-4, Kaytwo syrup, Eisai Co Ltd, Tokyo, Japan). We investigated association with other factors contributing to vitamin K deficiency. These plasma vitamin K concentrations varied greatly among the neonates from values below the limit of detection (2 ng/mL) to more than 1000 ng/mL. The vitamin K concentration was associated with nutritive vitamin K deficiency represented by plasma protein induced by vitamin K absence or antagonist-II (PIVKA-II) values. The wide variation in vitamin K absorption is considered to be one of the major causative factors in infantile vitamin K deficiency.

Administration, Oral↗
PubMed1991

Lipid peroxidation and benzo[a]pyrene activation to mutagenic metabolites: in vivo influence of vitamins A, E and C and glutathione in both dietary vitamin A sufficiency and deficiency.

Rats fed with either a sufficient-vitamin A or a vitamin A-free diet were pretreated with 750 mg/kg body weight of retinyl palmitate, alpha-tocopherol acetate, ascorbic acid or glutathione. Benzo[a]pyrene (BaP) metabolism and BaP-induced mutagenesis in Salmonella typhimurium TA98 were investigated and related to lipid peroxidation activities in postmitochondrial (S9) liver fraction. The microsomal mixed-function oxidase activities were decreased by vitamin A deficiency and weakly affected by scavenger treatment. The rate of lipid peroxidation of microsomal membranes was unaffected by vitamin A deficiency because of decreased polyunsaturated fatty acids and increased vitamin E contents. However, lipid peroxidation was decreased by pretreatment with fat-soluble vitamins (chiefly vitamin E) and increased by ascorbic acid. Within each experimental group both BaP metabolism and BaP mutagenic activity were closely correlated with the rate of lipid peroxidation. In vitamin A deficiency, the increased BaP metabolism and mutagenicity could be related to a decrease in cytosolic contents of scavengers (vitamin A and glutathione). In Ames test conditions, the free radical pathway became a route for BaP metabolism and thus the BaP activation to mutagenic metabolites is related to the cellular status in free radical scavengers.

Animals↗
PubMed2003

Reduction of plasma homocysteine and serum methylmalonate concentrations in apparently healthy elderly subjects after treatment with folic acid, vitamin B12 and vitamin B6: a randomised trial.

OBJECTIVES: To investigate, in an elderly population: (1) the effects of oral B-vitamin therapy on P-tHcys, S-MMA and Hb/MCV, (2) the appropriate decision limit for 'high' metabolite concentrations and (3) the estimated prevalence of vitamin B(12)/folate deficiency on the basis of different decision limits. DESIGN: Double-blind placebo-controlled intervention study. SETTING: Outpatient clinic. SUBJECTS: A total of 209 community-dwelling subjects, median age 76 y (range 70-93) y. INTERVENTION: Four months of oral daily supplementation with 0.5 mg cyanocobalamin, 0.8 mg folic acid and 3 mg vitamin B(6). RESULTS: High P- tHcys was found in 64% of men and 45% of women, high S-MMA in 11% of both. Vitamin B(12) deficiency was observed in 7.2% and folate deficiency in 11% of all subjects. Health-related upper reference limits for the metabolites at the start were higher than the laboratory's upper reference limits. The latter were, however, similar to those of the vitamin replete group. There was a significant decrease in P-tHcys (P<0.001) and S-MMA (P=0.009) after 4 months of vitamin treatment. In a multivariate analysis, the P-Hcys change correlated positively with baseline P-tHcys and inversely with baseline P-folate and transferrin saturation (Fe/TIBC ratio). The S-MMA change correlated with baseline S-MMA and inversely with baseline vitamin B(12) and age. CONCLUSIONS: Suboptimal vitamin status is an important cause of elevated P-tHcys and S-MMA in apparently healthy elderly subjects. Oral B-vitamin therapy is an effective and convenient way to normalise P-tHcys and S-MMA.

Aged↗
PubMed1995

A possible role of vitamin D receptors in regulating vitamin D activation in the kidney.

The vitamin D endocrine system is regulated reciprocally by renal 25-hydroxyvitamin D3 1 alpha- and 24-hydroxylases. Previously, we reported that renal proximal convoluted tubules, the major site of 1 alpha, 25-dihydroxyvitamin D3 production, have vitamin D receptors. In the presence of vitamin D receptors, renal proximal convoluted tubules cannot maintain the state of enhanced production of 1 alpha, 25-dihydroxyvitamin D3. To clarify this discrepancy, we proposed a working hypothesis for the reciprocal control of renal 25-hydroxyvitamin D3 1 alpha- and 24-hydroxylase activities. In rat models of enhanced renal production of 1 alpha, 25-dihydroxyvitamin D3, expression of vitamin D receptors and 25-hydroxyvitamin D3 24-hydroxylase mRNAs was strikingly suppressed in renal proximal convoluted tubules but not in the cortical collecting ducts. In vitamin D-deficient rats with up-regulated renal 25-hydroxyvitamin D3 1 alpha-hydroxylase activity, expression of vitamin D receptor mRNA in renal proximal convoluted tubules was also down-regulated, indicating that the down-regulation of vitamin D receptor mRNA is not the result of the enhanced production of 1 alpha, 25-dihydroxyvitamin D3. In Japanese quail models with up-regulated renal 25-hydroxyvitamin D3 1 alpha-hydroxylase activity by sex steroids, expression of vitamin D receptor mRNA was also down-regulated in the kidney but not in the duodenum. These results suggest that the down-regulation of vitamin D receptors plays a critical role in production of 1 alpha, 25-dihydroxyvitamin D3 in renal proximal convoluted tubules.

Animals↗
PubMed1993

High dose vitamin A supplementation of breast-feeding Indonesian mothers: effects on the vitamin A status of mother and infant.

For regions where vitamin A deficiency is common, high dose vitamin A supplementation of lactating mothers is currently recommended, but the effects of this intervention have not been carefully evaluated. We conducted a randomized, double-blind trial in which 153 Indonesian mothers 1-3 wk postpartum received either a capsule containing 312 mumol of vitamin A as retinyl palmitate or a placebo. Mothers' serum retinol concentrations in the vitamin A group tended to be lower than in the placebo group at baseline but higher at 3 mo postpartum (1.39 vs. 1.24 mumol/L, P = 0.03) and 6 mo postpartum (1.23 vs. 1.08 mumol/L, P < 0.01). The milk retinol concentrations of the vitamin A group were higher than those of the placebo group by 0.48 to 1.18 mumol/L at 1-8 mo postpartum (P < 0.05). Among the infants at 6 mo of age, the prevalences of low serum retinol concentration (< 0.52 mumol/L) were 36 and 15% in the placebo and vitamin A groups, respectively (P < 0.005), and the prevalences of low vitamin A stores (assessed by relative dose response) were 23 and 10%, respectively (P < 0.03). High dose vitamin A supplementation of lactating mothers is an efficacious way to improve the vitamin A status of both mother and breast-fed infant.

Adolescent↗
PubMed2002

Vitamin A supplementation of women postpartum and of their infants at immunization alters breast milk retinol and infant vitamin A status.

Vitamin A supplementation of lactating mothers and of infants at the time of diphtheria-pertussis-tetanus (DPT) and oral polio vaccine (OPV) immunizations have both been suggested as measures to prevent deficiency among infants. This multicenter randomized, double-blind, placebo-controlled trial was conducted in Ghana, India and Peru to determine the effect of maternal vitamin A supplementation on breast milk retinol and of maternal and infant supplementation on infant vitamin A status. Mothers in the intervention group received 60 mg vitamin A (as retinol palmitate) at 18-42 d postpartum; their infants were given 7.5 mg three times, i.e., at 6, 10 and 14 wk of age with DPT and OPV immunizations. Mothers and infants in the comparison group received a placebo. Maternal supplementation resulted in higher breast milk retinol at 2 mo postpartum [difference in means 7.1, 95% confidence interval (CI), 3.4, 10.8 nmol/g fat] and lower proportion of mothers with breast milk retinol < or = 28 nmol/g fat (15.2 vs. 26.6%, 95% CI of difference -16.6, -4.1%). At 6 and 9 mo, maternal supplementation did not affect breast milk retinol or the proportion of mothers with low breast milk retinol. Vitamin A supplementation of the mothers and their infants reduced the proportion of infants with serum retinol < or = 0.7 micro mol/L (30.4 vs. 37%, 95% CI of difference -13.7, 0.6%) and that with low vitamin A stores as indicated by the modified relative dose response (MRDR) > 0.06 (44.2 vs. 52.9%, 95% CI of difference -16.6, -0.9%) at 6 mo. Supplementation had no effect at 9 mo. The beneficial effect of supplementation on breast milk retinol and infants' vitamin A status varied by site. It was greatest in India followed by Ghana and Peru. At the doses used, maternal supplementation improved breast milk retinol status at 2 mo (P < 0.001) and maternal and infant supplementation modestly increased (P = 0.03) infant vitamin A status at 6 mo of age. Additional strategies to improve vitamin A status of 6- to 9-mo-old infants must be considered.

Adult↗
PubMed1998

Influence of vitamin A supplementation in milk on growth, health, concentrations of vitamins in plasma, and immune parameters of calves.

Seventy-seven Holstein calves were used to determine effects of vitamin A supplementation (0, 15,000, or 30,000 IU/d) of milk fed to calves through 6 wk of age. Effects of gender of calves and parity of dams also were considered. Supplementation with vitamin A did not affect retinol concentrations in plasma; however, calves fed milk containing supplemental vitamin A had decreased alpha-tocopherol concentrations in plasma at 6 wk compared with the concentrations in plasma of calves that were fed milk without supplemental vitamin A. Growth, serum protein, serum immunoglobulin (Ig) M and IgG, leukocyte proportions, and weekly fecal scores were not affected by vitamin A supplementation. Calves that scoured were fed milk supplemented with an additional 0 or 30,000 IU/d of vitamin A. Supplementation with an additional 30,000 IU/d when calves were scouring increased treatment days. Female calves had lower body measurements (weight, length, and height) at birth and greater fecal scores for wk 2 and 3 than did male calves. Gender did not affect serum protein, IgM, or IgG; however, female calves had higher percentages of monocytes and lower percentages of T cells than did male calves. At 6 wk, female calves also had higher percentages of B cells than did male calves. These data indicate that ratios of vitamins A and E should be considered in dietary formulations for calves. Also, additional vitamin A provided by some scour treatments could be detrimental to calves that are already receive vitamin A supplementation.

Animals↗
PubMed2005

Beyond vitamin E supplementation: an alternative strategy to improve vitamin E status.

Vitamin E has many reported health effects and is recognized as the most important lipid-soluble, chain-breaking antioxidant in the body. Vitamin E has also been reported to play a regulatory role in cell signalling and gene expression. Epidemiological studies show that high blood concentrations of vitamin E are associated with a decreased risk of cardiovascular diseases and certain cancers. Yet, high doses of supplemental vitamin E have been associated with an elevated risk of heart failure and all-cause mortality. Therefore, establishing alternative strategies to improve vitamin E status without potentially increasing mortality risk may prove important for optimal nutrition. To identify dietary phenolic compounds capable of increasing blood and tissue concentrations of vitamin E, selected polyphenols were incorporated into standardized, semi-synthetic diets and fed to male Sprague-Dawley rats for 4 weeks. Blood plasma and liver tissue concentrations of alpha-T and gamma-Twere determined. The flavanols (+)-catechin and (-)-epicatechin, the flavonol quercetin, and the synthetic preservative butylated hydroxytoluene (BHT) markedly elevated the amount of alpha-T in plasma and liver. The sesame lignan sesamin and cereal alkylresorcinols substantially increased the concentrations of gamma-T, but not alpha-T, in the liver. Sesamin also increased gamma-T concentrations in plasma. In order to study the impact of selected polyphenols on the enzymatic degradation of vitamin E, HepG2 cells were incubated together with phenolic compounds in the presence of tocopherols and the formation of metabolites was determined. Sesamin, at concentrations as low as 2 microM, almost completely inhibited tocopherol side-chain degradation and cereal alkylresorcinols inhibited it, dose-dependently (5-20 microM), by 20-80%. BHT, quercetin, (-)-epicatechin, and (+)-catechin had no effect on tocopherol-omega-hydroxylase activity in HepG2 cells. In order to confirm the inhibition of gamma-T metabolism by sesame lignans in humans, sesame oil or corn oil muffins together with deuterium-labelled d6-alpha-Tand d2-gamma-Twere given to volunteers. Urine samples were collected for 72 h and analysed for deuterated and non-deuterated tocopherol metabolites. Consumption of sesame oil muffins significantly reduced the urinary excretion of d2-gamma-CEHC and total (sum of labelled and unlabelled) gamma-CEHC. Overall, the findings from these studies show that the tested dietary phenolic compounds increase vitamin E concentrations through different mechanisms and, thus, have the potential to improve vitamin E status without the use of vitamin E supplements.

Animals↗