[Skip to Content]
[Skip to Content Landing]
Other Articles
June 4, 1938

VITAMIN A REQUIREMENTS AND PRACTICAL RECOMMENDATIONS FOR VITAMIN A INTAKE

Author Affiliations

WASHINGTON, D. C.

From the Bureau of Home Economics, U. S. Department of Agriculture.

JAMA. 1938;110(23):1920-1925. doi:10.1001/jama.1938.62790230008013
Abstract

The estimation of vitamin A requirements necessitates the measurement of some physical or chemical criteria dependent on vitamin A intake. The known specific criteria which characterize a vitamin A deficiency in the animal organism have been summarized by Bessey and Wolbach.1 Of the several recognized signs of vitamin A deficiency, it now appears that hemeralopia, or partial night blindness, is the earliest to appear. Fortunately it is a condition which lends itself readily to physical measurement. The amount of vitamin A that will just prevent hemeralopia probably represents something a little less than the minimum requirement. Certainly the vitamin A intake should not fall below the level that will be sufficient to prevent night blindness. A liberal margin of safety should be allowed for physiologic variations and for enabling the organism to lay by a store of this vitamin against such emergencies as illnesses attended with low or restricted

First Page Preview View Large
First page PDF preview
First page PDF preview
×