Dietary vitamin C supplementation and plasma vitamin E levels in humans

Vitamin E is believed to play a preventive role in diseases associated with oxidative stress. The aims of the present study were to quantify vitamin E intake levels and plasma concentrations and to assess dietary vitamin E adequacy in Irish adults. Intake data from the National Adult Nutrition Survey were used; plasma samples were obtained from a representative cohort of survey participants. Plasma α- and γ-tocopherol concentrations were measured by HPLC. The main sources of vitamin E in the diet were ‘butter, spreadable fats and oils’ and ‘vegetables and vegetable dishes’. When vitamin E intake from supplements was taken into account, supplements were found to be the main contributor, making a contribution of 29·2 % to vitamin E intake in the total population. Supplement consumers had significantly higher plasma α-tocopherol concentrations and lower plasma γ-tocopherol concentrations when compared with non-consumers. Consumers of ‘vitamin E’ supplements had significantly higher vitamin E intake levels and plasma α-tocopherol concentrations compared with consumers of other types of supplements, such as multivitamin and fish oil. Comparison with the Institute of Medicine Estimated Average Requirement of 12 mg/d indicated that when vitamin E intake from food and supplement sources was taken into account, 100 % of the study participants achieved the recommended intake levels. When vitamin E intake from food sources was taken into account, only 68·4 % of the females were found to achieve the recommended intake levels compared with 99·2 % of the males. The results of the present study show that dietary vitamin E intake has a significant effect on plasma α- and γ-tocopherol concentrations. Furthermore, they show that the consumption of supplements is a major contributor to overall intake and has a significant effect on plasma vitamin E concentrations in the Irish population.

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Vitamin C intake and susceptibility to the common cold

British Journal Of Nutrition ◽

10.1017/s0007114500002889 ◽

1997 ◽

Vol 77 (1) ◽

pp. 59-72 ◽

Cited By ~ 60

Author(s):

Harri Hemilä

Keyword(s):

Vitamin C ◽

Common Cold ◽

Potential Effect ◽

Dietary Vitamin ◽

High Dose ◽

Plasma Vitamin ◽

Vitamin C Supplementation ◽

The Common ◽

The Uk

Although the role of vitamin C in common cold incidence had been studied extensively, the level of vitamin C intake has not been unequivocally shown to affect the incidence of colds. In the present study the six largest vitamin C supplementation (≥ 1 g/d) studies, including over 5000 episodes in all, have been analysed, and it is shown that common cold incidence is not reduced in the vitamin C-supplemented groups compared with the placebo groups (pooled rate ratio (RR) 0·99; 95% CI 0·93, 1·04). Consequently these six major studies give no evidence that high-dose vitamin C supplementation decreases common cold incidence in ordinary people. Nevertheless, the analysis was continued with the hypothesis that vitamin C intake may affect common cold susceptibility in specific groups of people. It was assumed that the potential effect of supplementation might be most conspicuous in subjects with low dietary vitamin C intake. The average vitamin C intake has been rather low in the UK and plasma vitamin C concentrations are in general lower in males than in females. In four studies with British females vitamin C supplementation had no marked effect on common cold incidence (pooled RR 0·95; 95% CI 0·86, 1·04). However, in four studies with British male schoolchildren and students a statistically highly significant reduction in common cold incidence was found in groups supplemented with vitamin C (pooled RR 0·70; 95% CI 0·60, 0·81). Thus, these studies with British males indicate that vitamin C intake has physiological effects on susceptibility to common cold infections, although the effect seems quantitatively meaningful only in limited groups of people and is not very large.

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Effect of a blueberry nutritional supplement on macronutrients, food group intake, and plasma vitamin E and vitamin C in US athletes

International Journal of Food Sciences and Nutrition ◽

10.1080/09637480701550176 ◽

2008 ◽

Vol 59 (4) ◽

pp. 327-338 ◽

Cited By ~ 4

Author(s):

>Concepción Sánchez-Moreno ◽

Victoria A. Kimler ◽

Francie L. Cordts ◽

Jayne A. Cady ◽

Mary A. Weller ◽

...

Keyword(s):

Vitamin E ◽

Vitamin C ◽

Nutritional Supplement ◽

Food Group ◽

Plasma Vitamin ◽

Plasma Vitamin E

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SUPPLEMENTAL VALUE OF ASCORBIC ACID DURING LATE GESTATION ON PIGLET SURVIVAL AND EARLY GROWTH

Canadian Journal of Animal Science ◽

10.4141/cjas83-077 ◽

1983 ◽

Vol 63 (3) ◽

pp. 683-687 ◽

Cited By ~ 5

Author(s):

E. R. CHAVEZ

Keyword(s):

Ascorbic Acid ◽

Vitamin C ◽

Late Gestation ◽

Dietary Vitamin ◽

Control Group ◽

Plasma Vitamin ◽

Significant Difference ◽

Vitamin C Supplementation ◽

Dietary Treatments ◽

Piglet Survival

Twenty-six pregnant sows were included in four different dietary treatments as follows: (1) Control group with no vitamin C supplementation; (2) vitamin-C-supplemented group receiving 1 g/day ascorbic acid provided in a gelatin capsule; or (3) vitamin-C-supplemented group receiving 1 g/day ascorbic acid in a powder form spread on the top of the pelleted meal; (4) as (3) but receiving 10 g/day ascorbic acid. Vitamin-C-supplemented sows in treatments 2 and 4 showed a significant (P < 0.05) increase in blood plasma vitamin C prefarrowing. Pregnant sows receiving 10 g/day vitamin C supplement showed a significantly (P < 0.05) higher concentration of this vitamin in the urine than either control or sows receiving 1 g/day vitamin C supplementation. Sows in treatment 4 showed a significantly higher (P < 0.05) vitamin C content in colostrum than control animals. During lactation, no significant difference in vitamin C content in milk was observed between control and animals receiving 10 g/day vitamin C supplement. The vitamin C content in the plasma of the piglets at birth indicated that supplementing vitamin C to the mothers, significantly (P < 0.05) increased the concentration of this vitamin in the newborn piglet compared to control animals. However, the piglet survival and growth up to weaning at 3 wk of age was not significantly affected by dietary vitamin C supplementation of the mothers' diet. Key words: Ascorbic acid, gestation, piglet survival, Vitamin C

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Glutathione peroxidase activity and erythrocyte stability in calves differing in selenium and vitamin E status

British Journal Of Nutrition ◽

10.1079/bjn19810040 ◽

1968 ◽

Vol 46 (2) ◽

pp. 345-355 ◽

Cited By ~ 27

Author(s):

R. C. Siddons ◽

C. F. Mills

Keyword(s):

Vitamin E ◽

Glutathione Peroxidase ◽

Peroxidase Activity ◽

Dietary Vitamin ◽

Plasma Vitamin ◽

Glutathione Peroxidase Activity ◽

Bull Calves ◽

Plasma Vitamin E ◽

Erythrocyte Stability ◽

Vitamin E Status

1. Glutathione peroxidase activity (EC1.11.1.9) and erythrocyte stability were measured in Friesian bull calves which were given for 36 weeks semi-purified diets either adequate or low in selenium or vitamin E or both.2. Dietary Se or vitamin E content had no effect on growth rate and haematological vaiues. None of the calves exhibited clinical deficiency symptoms and serum aspartate amino transferase (EC 2.6.1.1) and creatine phosphokinase (EC 2.7.3.2) activities remained normal. Heart and skeletal muscles of all calves appeared macroscopically and microscopically normal at autopsy.3. Glutathione peroxidase activity in plasma, blood and other tissues, except the testis, was significantly lower in calves receiving low dietary Se but was independent of dietary vitamin E content.4. Plasma vitamin E levels decreased rapidly and to very low levels in calves given low vitamin E diets irrespective of the Se content of the diet.5. A low dietary vitamin E intake increased the susceptibility of erythrocytes to auto- and peroxidative haemolysis whereas a low Se intake in the presence of adequate vitamin E did not. However, erythrocytes from calves receiving low Se and low vitamin E were more susceptible to peroxidative haemolysis than erythrocytes from calves receiving low vitamin E and adequate Se. The effect of dietary vitamin E content on osmotic haemolysis induced by hypotonic saline was variable.6. The results suggest that measurement of blood glutathione peroxidase activity and the susceptibility of erythrocytes to auto- or peroxidative haemolysis could be used for the differential diagnosis of subclinical Se and vitamin E deficiency in ruminants.

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Effect of high concentrations of dietary vitamin e during various age periods on performance, plasma vitamin e and meat stability of broiler chicks at 7 weeks of age

British Poultry Science ◽

10.1080/00071669208417477 ◽

1992 ◽

Vol 33 (2) ◽

pp. 393-402 ◽

Cited By ~ 41

Author(s):

I. Bartov ◽

M. Frigg

Keyword(s):

Vitamin E ◽

Dietary Vitamin ◽

Plasma Vitamin ◽

Broiler Chicks ◽

High Concentrations ◽

Plasma Vitamin E

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Biohydrogenation of dietaryn-3 PUFA and stability of ingested vitamin E in the rumen, and their effects on microbial activity in sheep

British Journal Of Nutrition ◽

10.1079/bjn20031078 ◽

2004 ◽

Vol 91 (4) ◽

pp. 539-550 ◽

Cited By ~ 61

Author(s):

S. Chikunya ◽

G. Demirel ◽

M. Enser ◽

J. D. Wood ◽

R. G. Wilkinson ◽

...

Keyword(s):

Vitamin E ◽

Fish Oil ◽

Microbial Activity ◽

Latin Square ◽

Tocopheryl Acetate ◽

Dietary Vitamin ◽

Plasma Vitamin ◽

Plasma Vitamin E ◽

The Stability ◽

Oil Blend

The present study investigated the susceptibility of dietaryn-3 PUFA to ruminal biohydrogenation, the stability of ingested vitamin E in the rumen and the subsequent uptake of PUFA and vitamin E into plasma. Six cannulated sheep were assigned to six diets over five 33d periods, in an incomplete 6×5 Latin square. The diets, based on dried grass, were formulated to supply 50g fatty acids/kg DM using three lipid sources: Megalac®(calcium soap of palm fatty acid distillate; Volac Ltd, Royston, Herts., UK), linseed (formaldehyde-treated; Trouw Nutrition, Northwich, Ches., UK) and linseed–fish oil (formaldehyde-treated linseed+fish oil). The diets were supplemented with 100 or 500mg α-tocopheryl acetate/kg DM. Fat source or level of vitamin E in the diet did not alter microbial activity in the rumen. Biohydrogenation of linoleic acid (18:3n-6; 85–90%), linolenic acid (18:3n-3; 88–93%), docosahexaenoic acid (22:6n-3; 91%) and EPA (20:5n-3; 92%) was extensive. Feeding formaldehyde-treated linseed elevated concentrations of 18:3n-3 in plasma, whilst 22:6n-3 and 20:5n-3 were only increased by feeding the linseed–fish oil blend. Duodenal recovery of ingested vitamin E was high (range 0·79–0·92mg/mg fed). High dietary vitamin E was associated with increased plasma α-tocopherol (2·57v.1·46μg/ml for 500 and 100mg α-tocopheryl acetate/kg DM respectively), although all concentrations were low. Plasma vitamin E levels, however, tended to decrease as the type and quantity of PUFA in the diet increased. The present study illustrates that nutritionally beneficial PUFA in both fish and linseed oils are highly susceptible to biohydrogenation in the rumen. Although α-tocopheryl acetate resisted degradation in the rumen, plasma vitamin E status remained deficient to borderline, suggesting either that uptake may have been impaired or metabolism post-absorption increased.

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Effect of forage type and supplemental dietary vitamin E on milk oxidative stability

Canadian Journal of Animal Science ◽

10.4141/cjas91-139 ◽

1991 ◽

Vol 71 (4) ◽

pp. 1181-1186 ◽

Cited By ~ 22

Author(s):

J. W. G. Nicholson ◽

Anne-Marie St-Laurent

Keyword(s):

Vitamin E ◽

Oxidative Stability ◽

Corn Silage ◽

Dietary Vitamin ◽

Plasma Vitamin ◽

Forage Type ◽

Alfalfa Silage ◽

Plasma Vitamin E ◽

Spontaneous Oxidation ◽

Vitamin E Supplementation

Twelve Holstein cows in each of two replicates were used to determine the effect of forage type and vitamin E supplementation on the oxidative stability of milk. Alfalfa or corn silage was fed ad libitum as the sole roughage, with a concentrate to milk ratio of 1:2.5. Half the cows on each forage were fed 7000 IU d−1 of dL-α-tocopherol acetate top-dressed on the concentrate in two feedings per day over a 4-wk period. Cows consuming the alfalfa silage had higher (P < 0.05) plasma vitamin E content, but there were no differences in milk vitamin E or flavor due to forage type. Supplementing the diets with vitamin E resulted in higher (P < 0.01) vitamin E content of plasma and milk and improved milk oxidative stability. There was an interaction (P = 0.03) between forage type and vitamin E supplementation for oxidative flavor score in week 2. Supplementing the corn silage diet with 7000 IU d−1 of vitamin E resulted in almost complete elimination of oxidized flavor in milk within 1 wk of starting supplementation. However, supplementing the alfalfa silage diet had no effect on flavor over the first 3 wk of feeding. It is apparent that the vitamin E content of milk is not the sole determinant of its oxidative stability. Key words: Spontaneous oxidation, flavor, milk, vitamin E, alfalfa, corn silage, cow

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