VITAMIN A CONTENT OF FRESH EGGS 1 
By Joseph C. Murphy, Junior Chemist , and JD. Breese Jones, Senior Chemist 
in Charge, Protein Investigation Laboratory , Bureau of Chemistry , United States 
Department of Agriculture 
The significance of vitamins from the 
general standpoint of health and nutri¬ 
tion is now so well established that all 
new data on their content in foods are 
of prime importance. Several charac¬ 
teristic diseases and functional dis¬ 
orders are associated with a lack or 
deficiency of specific vitamins in the 
diet. Among these are beriberi, xer¬ 
ophthalmia, scurvy, rickets, impair¬ 
ment of the process of reproduction, 
failure of growth in youngf animals, and 
decline in weight in adults. The 
different vitamins are so distributed in 
our common food products that the 
diet of the average person probably 
contains an adequate supply. Never¬ 
theless, through force of circumstances 
or on account of individual preference, 
many persons live on a diet so re¬ 
stricted that these food accessories are 
not obtained in sufficient quantities to 
meet nutritional requirements or to 
insure the optimum of health and well¬ 
being. This is particularly true in the 
case of small children. Cramer (3) 2 
has recently pointed out that a border¬ 
land between health and disease may 
be created by a restriction in the 
vitamin supply. A diet may contain 
enough vitamins to afford protection 
from obvious ill health or interference 
with the breeding and rearing of the 
stock, and yet be so restricted as to 
lead to imperfect development and 
deviations from the optimum which 
up to the present have been overlooked. 
It is becoming increasingly recog¬ 
nized that deficiency diseases and 
disorders caused by an insufficient 
intake of vitamins are of more frequent 
occurrence than has been generally 
supposed. Cramer (3) refers to out¬ 
breaks of an eye affection in England 
which have been ascribed to a lack of 
sufficient vitamin A and which were 
eliminated by the administration of 
cod liver oil. An account has also 
recently been given by Bloch ( 1) of a 
surprisingly large number of cases of 
xerophthalmia among children in Den¬ 
mark who had not been getting suffi¬ 
cient vitamin A. The large number 
of cases of malnutrition among chil¬ 
dren in our public schools, and the 
beneficial effects produced by the re¬ 
cently introduced practice in many 
schools of furnishing milk, emphasize 
the need of greater attention to the 
qualitative and quantitative composi¬ 
tion of the dietary. 
It has been aptly stated that “vita¬ 
mins should be obtained from the dairy, 
the grocery and the market, not from 
the drug store.” Among the best 
known sources of vitamin A are cod- 
liver oil, butterfat, spinach, tomatoes, 
and egg yolk. From the standpoint of 
the health and nutrition of the general 
public the importance of any particular 
foodstuff as a source of vitamin must 
be considered from certain other angles 
as well as from its vitamin content. 
Of two substances having the same 
vitamin content, that one will be of 
the greater general importance which 
is the less expensive; which is more 
readily available to all people at all 
seasons and in all places; which com¬ 
bines with its vitamin value the greater 
food value with respect to other dietary 
factors; which is the more digestible, 
the more palatable, and better tolerated 
by infants and invalids. In accordance 
with these considerations, eggs must 
be considered a very important, if not 
the most important, source of vitamin 
A. Eggs and milk are the two articles 
which in themselves come nearest to 
being perfect foods. They contain all 
of the dietary factors essential for the 
nutrition of an animal during the early 
stages of its existence. 
Hess' (4) found that egg yolk is well 
tolerated by babies. He reported that 
for six months about 50 babies were fed 
with excellent results a mixture con¬ 
sisting of milk (24 oz.), barley water 
(12 oz.), sugar oz.), and 1 egg yolk; 
and he states that “egg yolk possesses 
marked antirachitic properties—far 
more than any other natural food 
product (5).” That egg yolk is a rich 
source of vitamin A was pointed out by 
Osborne and Mendel (7) and by 
McCollum and Davis ( 6 ) in their early 
work on this vitamin. Working with 
the yolk of fresh eggs, Hess found that 
0.25 gm. fed daily was sufficient to 
protect rats from rickets. Casparis, 
1 Received for publication July 11, 1924; issued January, 1925. This paper was presented at the 67th 
meeting of the American Chemical Society held in Washington, D. C., Apr. 21 to 26, 1924. 
2 Reference is made by number (italic) to “Literature cited,” p. 257. 
Journal of Agricultural Research, 
Washington, D. C. 
( 253 ) 
Vol. XXIX, No. 5 
Sept. 1,1924 
Key No E—31 
