5. Immunity problems:
Repeat infections such as sinusitis,
ear infections, candidiasis, fungal infections, and particularly,
Poor recovery from infections such as flu
and colds or sores.
6. Reproductive problems:
Impairment of sperm formation in males.
Spontaneous abortion in
Impaired development of embryo
7. Failure to
grow, or growth retardation, is the most common sign in children.
Food Sources of Vitamin A
Excellent: Liver, chicken giblets, oysters, cod, halibut.
Milk, cheese, butter, eggs and other fish.
Very good: Carrot juice, sweet potato with peel, pumpkin, carrots.
Good: Dark green leafy vegetables such as spinach, collards, kale,
beet greens, turnip greens.
Recommended Daily Dietary
Allowances for Vitamin A:
Children 1 to 3 years: 600 micrograms
Males add females 19 years and older: 3,000 mcg
Drugs that increase blood levels of
vitamin A include Lescol, Mevacor, Provachol and Zocor, while those
that interfere with vitamin A absorption include Cholestyramine and
Contraceptives may increase blood levels of vitamin A.
Neomycin, an antibiotic, may decrease the absorption of vitamin A.
Impact of Storage, Processing, and Cooking
Vitamin A is
unaffected by light, heat and usual cooking methods. It is destroyed
by oxidation (exposure to air), drying, very high temperatures and
ultraviolet light. Keep food wrapped to protect it from air and
Excessive vitamin A may
interfere with vitamin K absorption.
Persistent high doses of vitamin A (not carotenoids) of over 14,000
IU in infants or 33,000 IU in adults overcomes the liverís ability
to store it and can produce toxicity. Children and people with
kidney failure are at high risk of toxicity and should always inform
their physician of any supplement use. Excessive alcohol consumption
increases toxicity. Toxic effects of vitamin A (in the form of
retinoic acid) exceeding 10,000 IU when used as a supplement by
pregnant women or as the active ingredient in acne products like
Accutane have been shown to cause malformations such as spina bifida
in their developing fetuses.
Symptoms of vitamin A toxicity
include dry lips is an early sign, followed by dryness of the nasal
tissues. Later signs include dryness, redness, scaling, and peeling
of skin, hair loss and nail fragility. Other symptoms can include
vomiting in infants and children, headache, nausea, bone pain,
fractures, fatigue and muscle pain.
vitamin A PAGE