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VITAMIN A
Vitamin A is
required by all children for proper growth, and by human beings of all
ages for the maintenance of the proper condition of the epithelial
tissues, as in respiratory, digestive, and urinary tracts and in glands
of internal secretion. It is also necessary for proper formation of the
teeth. Another function of this vitamin is its association with the
ability of a person to adjust his sight when going from a brightly
lighted place to a dark or dimly lighted one. It is essential for the
regeneration of visual purple in the eye, a phototropic substance in the
retina which is very sensitive to light. Vitamin A is associated with
the presence or absence of the deficiency disease known as night
blindness or the inability to see well after dark, but not all cases of
night blindness are associated with vitamin A deficiency.
There is a popular belief
that vitamin A prevents infection such as colds. From the present
medical point of view, however, this is not true in its strictest sense,
although a deficiency in vitamin A unquestionably lowers the resistance
of the body cells and may thereby be related in some measure to the
ability to withstand infection. If the body has a good store of vitamin
A, and the foods which one eats supply liberal amounts of this vitamin
daily, an additional amount of the vitamin will not produce further
increases in resistance to infection, as is believed in some quarters.
When animals, including
human beings, are deprived in large part of vitamin A, they cannot grow
or rebuild worn-out bodily tissues. Such delicate organs as the eyes,
when deprived of this vitamin, may likewise become affected by
infection. In extremely acute stages of vitamin A deficiency,
xerophthalmia, a serious eye disease which may cause complete and
permanent blindness if not arrested, is found in rare instances.
Rich food sources of
vitamin A are liver, butter, cream, eggs, some kinds of cheese, fish
liver oils, some fruits, and some vegetables, especially the green leafy
and the yellow vegetables.
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click for larger photo
Victory Gardens
Handbook of the
Victory Garden Committee
War Services, Pennsylvania
State Council of Defense
April, 1944
TABLE OF CONTENTS
page v
page vi
page vii
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