Erythrocyte Survival Time and Reticulocyte Levels After Tocopherol Depletion in Man

Horwitt, M. K.; Century, Bernard; Zeman, A.

doi:10.1093/ajcn/12.2.99

Cited by 91 publications

(29 citation statements)

References 16 publications

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“…Data investigating the relationship of the intake of the vitamin to chronic diseases were reviewed but could not be used to set DRVs. The Estimated Average Requirement (EAR) of 12 mg α-tocopherol/day was based on data on induced deficiency in men (Horwitt et al, 1956;Horwitt, 1960Horwitt, , 1962Horwitt et al, 1963;Horwitt et al, 1972;Horwitt, 1974;Farrell et al, 1977). In particular, IOM used and adapted data from Horwitt et al (1963) (instead of Farrell et al (1977)) to consider that a plasma α-tocopherol concentration of 12 µmol/L was associated with in vitro hydrogen peroxide-induced haemolysis below 12 % (which was considered normal).…”

Section: The Nordic Countries (Nordic Council Of Ministers 2014) Maimentioning

confidence: 99%

Scientific Opinion on Dietary Reference Values for vitamin E as α‐tocopherol

Products¹

2015

EFS2

111

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Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) derived Dietary Reference Values (DRVs) for vitamin E. In this Opinion, the Panel considers vitamin E as α-tocopherol only. The Panel considers that Average Requirements (ARs) and Population Reference Intakes (PRIs) for vitamin E (as α-tocopherol) cannot be derived for adults, infants and children, and therefore defines Adequate Intakes (AIs), based on observed intakes in healthy populations with no apparent α-tocopherol deficiency in the EU. This approach considers the range of average intakes of α-tocopherol and of α-tocopherol equivalents estimated by EFSA from dietary surveys in children and adults in nine countries. The Panel notes the uncertainties in the available food composition and consumption data, the fact that most EU food composition databases contain values for vitamin E as α-tocopherol equivalents, as well as the contribution of average α-tocopherol intakes to average α-tocopherol equivalent intakes in these countries. For adults, an AI for α-tocopherol is set at 13 mg/day for men and 11 mg/day for women. For children aged 1 to < 3 years, an AI for α-tocopherol is set at 6 mg/day for both sexes. For children aged 3 to < 10 years, an AI for α-tocopherol is set at 9 mg/day for both sexes. For children aged 10 to < 18 years, an AI for α-tocopherol is set at 13 mg/day for boys and 11 mg/day for girls. For infants aged 7-11 months, an AI for α-tocopherol of 5 mg/day is derived by extrapolating upwards from the estimated α-tocopherol intake in exclusively breast-fed infants aged 0-6 months and rounding. For pregnant or lactating women, the Panel considers that there is no evidence for an increased dietary α-tocopherol requirement, and the same AI is set as for non-pregnant non-lactating women. Vitamin E is a fat-soluble vitamin. Previously, the term vitamin E was used as the generic term for four tocopherols (α, β, γ, δ) and four tocotrienols (α, β, γ, δ), which are organic compounds that possess antioxidant activity to a different degree. Factors have been used to convert food contents of tocopherols and tocotrienols to α-tocopherol equivalents. In this Opinion, based on the available evidence and in line with other authoritative bodies, the Panel considers vitamin E as being α-tocopherol only. Its naturally occurring form is RRR-α-tocopherol. Commercially available forms of α-tocopherol include RRR-α-tocopherol, a synthetic form that contains in equal proportions the eight stereoisomers of α-tocopherol (RRR-, RRS-, RSR-, RSS-and their enantiomers SSS-, SSR-, SRS-, SRR-) and is called all-rac-α-tocopherol, and their esterified forms. © EuropeanEfficient α-tocopherol absorption requires the presence of fat. The Panel considered that the average α-tocopherol absorption from a usual diet is about 75 %. This is based on the means observed in two balance studies and in a kinetic study using a multi-compartmental model of α-tocopherol metabolism. After its intestinal absorption, α-toc...

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Section: The Nordic Countries (Nordic Council Of Ministers 2014) Maimentioning

confidence: 99%

Scientific Opinion on Dietary Reference Values for vitamin E as α‐tocopherol

Products¹

2015

EFS2

111

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“…Abnormal erythropoiesis, impaired iron metabolism and decreased erythrocyte survival times have also been observed in vitamin E-de®cient animals 130,133,134 . In humans, vitamin E supplementation has been shown to increase the reticulocyte count 135 . Preterm and low birth weight infants are born with low serum and tissue concentrations of vitamin E, due in part to limited placental transport of tocopherols and to scarcity of storage adipose tissue 129,136 .…”

Section: Vitamin Ementioning

confidence: 99%

The role of vitamins in the prevention and control of anaemia

Fishman

Christian

West

2000

Public Health Nutr.

264

208

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Objective: While iron de®ciency is regarded as the major cause of nutritional anaemia, changes in vitamins A, B 12 , C and E, folic acid and ribo¯avin status have also been linked to its development and control. This paper provides a systematic review of vitamin supplementation trials relating to the control of nutritional anaemia. Methods: A MEDLINE search was used to ®nd reports of vitamin supplementation trials that reported changes in anaemia or iron status. Results: Vitamin A can improve haematological indicators and enhance the ef®cacy of iron supplementation. Both folate and vitamin B 12 can cure and prevent megaloblastic anaemia. Ribo¯avin enhances the haematological response to iron, and its de®ciency may account for a signi®cant proportion of anaemia in many populations. Vitamin C enhances the absorption of dietary iron, although population-based data showing its ef®cacy in reducing anaemia or iron de®ciency are lacking. Vitamin E supplementation given to preterm infants has not reduced the severity of the anaemia of prematurity. Vitamin B 6 effectively treats sideroblastic anaemia. Multivitamin supplementation may raise haemoglobin (Hb) concentration, but few studies have isolated the effect of multivitamins from iron on haematological status. Conclusions: In general, the public health impact of vitamin supplementation in controlling anaemia is not clear. Neither are the complex interactions involving multiple vitamins in haematopoiesis suf®ciently understood to explain the observed variability in haematological responses to vitamins by age, population, vitamin mixture and dosages. Further research is needed to understand the roles of individual and combined vitamin de®ciencies on anaemia to design appropriate micronutrient interventions to prevent anaemia.

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“…The requirements for vitamin E intakes are therefore based primarily on studies in which plasma a-tocopherol concentrations and corresponding hydrogen peroxide-induced erythrocyte lysis were determined (Horwitt, 1960(Horwitt, , 1962(Horwitt, , 1974Horwitt et al, 1956Horwitt et al, , 1963Horwitt et al, , 1972. Vitamin E depletion in 19 normal, adult men was studied by feeding them a 2,200-kcal diet containing 3 mg (7 pmol)/day (range 2 to 4 mg [4.7 to 9.3 pmol]) of a-tocopherol and 55 g/day of fat (30 g from vitamin E-free lard) for 2.5 years.…”

Section: Plasma A-tocopherol Concentrations and Hydrogen Peroxideindumentioning

confidence: 99%

“…Differences up to this amount are not significant unless special precautions are taken to age and standardize the hydrogen peroxide solutions (Horwitt et al, 1963). The data in Figure 6-6 comparing long-term vitamin E-depletion in four subjects (depleted for more than 72 months) with six control subjects (Horwitt et al, 1963) show that at some concentration of plasma a-tocopherol between 6 pmol/L (258 pg/dL) and 12 pmol/L (516 ug/dL), an increase in hydrogen peroxide-induced hemolysis above 12 percent was observed in vitro. Averaging the a-tocopherol concentrations in the six subjects with hemolysis values of 12 percent or less in Figure 6-6 results in an average a-tocopherol concentration of 16.2 pmol/L (697 jig/dL).…”

Section: Plasma A-tocopherol Concentrations and Hydrogen Peroxideindumentioning

confidence: 99%

Establishment of Dietary Reference Intakes for Dietary Antioxidants

Meyers¹

2000

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Erythrocyte Survival Time and Reticulocyte Levels After Tocopherol Depletion in Man

Abstract: Ui a. ' nor "95 per cent life" values of the erythocytes between the depleted and control subjects. At ' '95 per cent Cr5'-life, ' ' relative elution rate effects are minimized and at ' 'total-life, ' ' the elution rate has no theoretic effect.

Cited by 91 publications

References 16 publications

Scientific Opinion on Dietary Reference Values for vitamin E as α‐tocopherol

Scientific Opinion on Dietary Reference Values for vitamin E as α‐tocopherol

The role of vitamins in the prevention and control of anaemia

Establishment of Dietary Reference Intakes for Dietary Antioxidants

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