Vitamin A (Oral Route, Intramuscular Route)

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Vitamin A (Oral Route, Intramuscular Route)

US Brand Names

Description

Vitamins are compounds that you must have for growth and health. They are needed in small amounts only and are usually available in the foods that you eat. Vitamin A is needed for night vision and for growth of skin, bones, and male and female reproductive organs. In pregnant women vitamin A is necessary for the growth of a healthy fetus.

Lack of vitamin A may lead to a rare condition called night blindness (problems seeing in the dark), as well as dry eyes, eye infections, skin problems, and slowed growth. Your health care professional may treat these problems by prescribing vitamin A for you.

Some conditions may increase your need for vitamin A. These include:

• Diarrhea
• Eye diseases
• Intestine diseases
• Infections (continuing or chronic)
• Measles
• Pancreas disease
• Stomach removal
• Stress (continuing)

In addition, infants receiving unfortified formula may need vitamin A supplements.

Vitamin A absorption will be decreased in any condition in which fat is poorly absorbed.

Increased need for vitamin A should be determined by your health care professional.

Claims that vitamin A is effective for treatment of conditions such as acne or lung diseases, or for treatment of eye problems, wounds, or dry or wrinkled skin not caused by lack of vitamin A have not been proven. Although vitamin A is being used to prevent certain types of cancer, some experts feel there is not enough information to show that this is effective, particularly in well-nourished individuals.

Injectable vitamin A is given by or under the supervision of a health care professional. Other forms of vitamin A are available without a prescription.

For good health, it is important that you eat a balanced and varied diet. Follow carefully any diet program your health care professional may recommend. For your specific dietary vitamin and/or mineral needs, ask your health care professional for a list of appropriate foods. If you think that you are not getting enough vitamins and/or minerals in your diet, you may choose to take a dietary supplement.

Vitamin A is found in various foods including yellow-orange fruits and vegetables; dark green, leafy vegetables; vitamin A-fortified milk; liver; and margarine. Vitamin A comes in two different forms, retinols and beta-carotene. Retinols are found in foods that come from animals (meat, milk, eggs). The form of vitamin A found in plants is called beta-carotene (which is converted to vitamin A in the body). Food processing may destroy some of the vitamins. For example, freezing may reduce the amount of vitamin A in foods.

Vitamins alone will not take the place of a good diet and will not provide energy. Your body needs other substances found in food, such as protein, minerals, carbohydrates, and fat. Vitamins themselves often cannot work without the presence of other foods. For example, small amounts of fat are needed so that vitamin A can be absorbed into the body.

The daily amount of vitamin A needed is defined in several different ways.

For U.S.—
• Recommended Dietary Allowances (RDAs) are the amount of vitamins and minerals needed to provide for adequate nutrition in most healthy persons. RDAs for a given nutrient may vary depending on a person's age, sex, and physical condition (e.g., pregnancy).
• Daily Values (DVs) are used on food and dietary supplement labels to indicate the percent of the recommended daily amount of each nutrient that a serving provides. DV replaces the previous designation of United States Recommended Daily Allowances (USRDAs).
• Normal daily recommended intakes in the United States for vitamin A are generally defined according to age or condition and to the form of vitamin A as follows:

Note: Based on 1980 U.S. Recommended Dietary Allowances (RDAs) for vitamin A in the diet that is a combination of retinol and beta-carotene.

For Canada—
• Recommended Nutrient Intakes (RNIs) are used to determine the amounts of vitamins, minerals, and protein needed to provide adequate nutrition and lessen the risk of chronic disease.
• Normal daily recommended intakes in Canada for vitamin A are generally defined according to age or condition and to the form of vitamin A as follows:

Note: Based on 1980 U.S. Recommended Dietary Allowances (RDAs) for vitamin A in the diet that is a combination of retinol and beta-carotene.

In the past, the RDA and RNI for vitamin A have been expressed in Units. This term Units has been replaced by retinol equivalents (RE) or micrograms (mcg) of retinol, with 1 RE equal to 1 mcg of retinol. This was done to better describe the two forms of vitamin A, retinol and beta-carotene. One RE of vitamin A is equal to 3.33 Units of retinol and 10 Units of beta-carotene. Some products available have not changed their labels and continue to be labeled in Units.

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