There are two forms of vitamin A, a fat-soluble nutrient.  One is preformed vitamin A, like retinol, which comes from dairy products, fish and meat.  The second is provitamin A carotenoids, like beta-carotene, that is obtained from plants.   Both types of vitamin A are stored in the liver.   In the body, beta-carotene acts as an antioxidant.

ANTIOXIDANT

Oxygen is vital to the body’s health, but oxygen can also create problems for the body by removing one or more electrons from an atom or molecule.  This process happens when our bodies convert the food we eat into energy.  This creates free radicals, especially reactive particles, that can damage other cells, proteins and DNA by altering them. We are also exposed to free radicals from smoke, air pollution and sunlight.

Vitamin A is used by the body to counter the negative effects of the free radicals.

USES IN THE BODY

Vitamin A is used by the body:
•    For maintenance of skin
•    For maintenance of teeth
•    For maintenance of skeletal tissue
•    For maintenance of soft tissue
•    For development and maintenance of the eyes
•    As an antioxidant
SYMPTOMS OF VITAMIN A DEFICIENCY

The symptoms most commonly associated with vitamin A deficiency are:
•    Vision problems
•    Macular degeneration
•    Dry Skin
•    Skin problems not healing normally
•    Weakening of nails
•    Diarrhea

SOURCES OF VITAMIN A

The most common foods containing vitamin A are:
•    Eggs
•    Meat
•    Cheese
•    Liver
•    Cod liver oil
•    Halibut oil
•    Herring
•    Salmon
•    Tuna
•    Chicken breast
•    Pistachio nuts
•    Cantaloupe
•    Pink grapefruit
•    Apricots
•    Mangos
•    Spinach
•    Broccoli
•    Black-eyed peas
•    Carrots
•    Pumpkin
•    Sweet potatoes
•    Supplements   [this is not a food?]

VITAMIN A AND DISEASE
While there are studies being conducted on the effects of vitamin A on cancer and heart disease, dementia and other health problems, there does not appear to be any scientific study that establishes the benefits of vitamin A in treating these health problems.

There have been some studies that indicated that vitamin A was helpful in slowing the progress of age-related macular degeneration.

RECOMMENDED DOSAGE

While doctors do not agree on the minimum amount of vitamin A that is required, most seem to agree that people should not take more than 2,500 international units daily, and some people can only tolerate a much lower amount.  The amount of vitamin A recommended will depend on whether a person is taking other drugs that might create unwanted problems and the person’s diet and lifestyle.

EXCESS VITAMIN A

Because any excess vitamin A obtained from animal sources, preformed vitamin A, is stored in the liver, this can create a toxic effect.  Interestingly, excess amounts of beta-carotene do not create the same toxic effect.  Some of the problems from excess vitamin A are:
•    Dizziness
•    Nausea
•    Headaches
•    Skin irritation
•    Joint pain
•    Birth defects
•    Death