Should Vitamin A Intakes Be Two- to Fivefold Higher than Currently …

Short Description
vitamin A in lu unhappily creates confusion, a situation. realized by the Food and Agriculture … applied to preformed vitamin A, can get one in trouble. …

Website: jn.nutrition.org | Filesize: 322kb

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Letters to the Editor
Should Vitamin A Intakes Be Two- to Fivefold Higher
than Currently Recommended?
Dear Dr. Hurley:
In his recent article on dietary standards (1), Hegsted
recommends a set of tentative energy-based dietary
standards for various nutrients and food components.
I wish to discuss several aspects of his recommendation
that adults should ingest 3500-4000 lu of vitamin A/
1000 kcal.
First, the need for vitamin A is not known to relate
to energy intake. Physiologically, vitamin A is primar
ily involved in vision and in cellular differentiation,
functions that can readily be related to growth and
roughly related to body mass but not to total energy
expenditure. Although various stresses can increase the
catabolism of vitamin A, expressing the need for vi
tamin A as a function of energy utilization can be very
misleading indeed.
Second, the expression of recommended intakes of
vitamin A in lu unhappily creates confusion, a situation
realized by the Food and Agriculture Organization/World
Health Organization Expert Committee on Vitamin A
in 1967 and the RDA (Recommended Dietary Allow
ances) Committees in the United States in 1974 and
1980. As a result, these groups instead employed the
term retinol…