Nutritional Deficiencies
Vitamin A -
updated: 17 November 2008
Vitamin A intake and status
Eur J Clin Nutr. 1996 Jul;50 Suppl 3:S7-12
van den Berg H.
OBJECTIVE: To review the methodology for vitamin A intake and status assessment and to discuss available data on vitamin A intake and status in the Netherlands. CONCLUSIONS: For diagnosis of a deficient vitamin A status, a number of valid biochemical and functional tests and criteria for interpretation are available. However, the sensitivity and specificity of most tests for assessment of the vitamin A status in the suboptimal and/or marginal range seem troublesome. The average vitamin A intake in the Netherlands (adult men 830 RE; adult women 650 RE) is slightly below the Dutch RDA (men 1000 RE; women 800 RE. In particular, individuals avoiding liver and liver products have lower intakes and might have limited stores. The functional significance of these findings remains to be established
Publication Types:
Online - Abstract
Nutrition and health--vitamins and vitamin supplements
Ned Tijdschr Geneeskd. 2003 Apr 19;147(16):752-6
Schrijver J, van den Berg H.
A balanced diet based on the Guidelines of the Netherlands Nutrition Centre provides a suitable basis for the maintenance of good health. However, there are a number of situations where supplementation with vitamins is clearly indicated. These include infants (vitamin A, D and K), young children, and pregnant and lactating women (vitamin D), future expectant mothers (folic acid) and the elderly (vitamin D). If doubts exist about a sufficient vitamin intake via the regular diet, a daily supplement supplying all vitamins at the level of the recommended daily allowance (RDA) is considered to be a responsible and safe choice. Epidemiological research indicates that the incidence of certain diseases is lower if the intake of vitamins is significantly higher than the RDA. However to date, targeted intervention studies have provided little unequivocal evidence to support this argument. For certain vitamins (A, D, folic acid, B6, nicotinic acid and beta-carotene) excessive intakes are associated with a health risk or clear toxicity. In the case of vitamin B6, nicotinic acid, folic acid and beta-carotene this risk is mainly limited to the use of high-dose supplements.
Publication Types:
Online - Abstract
Evaluation of the effect of the use of vitamin supplements on vitamin A intake among (potentially) pregnant women in relation to the consumption of liver and liver products
Eur J Obstet Gynecol Reprod Biol. 1996 May;66(1):17-21
van den Berg H, Hulshof KF, Deslypere JP.
OBJECTIVE: To assess the distribution of dietary vitamin A intake among Dutch women aged 16-50 and among pregnant women, and to evaluate the effect of the use of a vitamin A (1200 RE) containing multivitamin supplement in terms of nutritional and teratogenic risk. STUDY DESIGN: Data from the 2nd Dutch national food consumption survey (1992) were used for calculation of the vitamin A intake among 1725 16-50 year old women and 58 pregnant women. Calculations were performed with and without simulation of the use of a supplement containing 1200 RE vitamin A. RESULTS: Average vitamin A intake, based on a two-day dietary record method, compared quite well with recommended intake levels: 850 RE for the 16-50 year old non-pregnant (NP) women (RDA: 800 RE), and 990 RE for the pregnant (P) women (RDA: 1000 RE), respectively. The use of liver on one of the days under survey resulted in high intakes: 60% of the women in this subgroup exceeded the 'safe upper intake limit' of 3000 RE, while in 23% of the cases intakes were > 7500 RE. Those not consuming liver or liver products on the days under survey had relatively low average intakes [NP (n = 1472): 540 RE; P (n = 46): 720 RE]; about 70% of the non-liver users had intakes below the RDA. Including the daily use of a vitamin A containing multivitamin supplement with 1200 RE resulted in intakes > RDA, while only in 2% (NP), respectively 3% (P) of the cases the 'total' intake exceeded the 3000 RE level, but remained in all cases below 7500 RE/day. serving per day. CONCLUSION: The use of a vitamin A containing (maximum 1200 RE) multivitamin supplement can contribute to a controlled and adequate vitamin A intake and be considered as safe for pregnant women or women who wish to become pregnant, if the consumption of liver is completely avoided and the consumption of liver products is limited to maximum one.
Publication Types:
Online - Abstract
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