Vitamin A
Recommended Intake
Vitamin A Deficiency
Vitamin A Toxicity
Major Food Sources
Antioxidant Capabilities
Tips for Increasing Your Vitamin A Intake

Vitamin A, also called retinol, is a fat-soluble vitamin. Fat-soluble vitamins are stored in the body in the liver and fatty tissues. The active form of vitamin A is found in animal tissue. Red, orange, and dark green vegetables and fruits contain a precursor form of vitamin A called carotenoids, which can be converted into vitamin A in the body.

Vitamin A's functions include:

• playing an essential role in vision
• playing an important role in cell differentiation and cell division
• helping in the formation and maintenance of healthy skin and hair
• helping with proper bone growth and tooth development
• helping the body regulate the immune system
• playing an essential role in the reproduction process for both men and women

Recommended Intake:

Vitamin A Deficiency
Symptoms of vitamin A deficiency include:

• night blindness
• dry skin
• dry hair, broken fingernails
• follicular keratinosis - hardened, pigmented goose bumps on the arms, legs, and hair follicles
• decreased resistance to infections
• loss of appetite
• decreased growth rate

The following populations may be at risk for vitamin A deficiency and may require a supplement:

• People with a reduced ability to absorb dietary fat; because vitamin A is a fat-soluble vitamin, fat is required for its absorption. Some conditions that can cause fat malabsorption include Crohn's disease, cystic fibrosis, celiac disease, pancreatic enzyme deficiency, and liver disease.
• Children living at or below the poverty level. This is especially critical in areas with high incidence of measles.

Vitamin A Toxicity
As a fat-soluble vitamin, vitamin A is stored in the body and not excreted in the urine like most water-soluble vitamins. Therefore, it is possible for vitamin A to accumulate in the body and reach toxic levels. The tolerable upper intake level (UL) for vitamin A from dietary sources and supplements combined is 3,000 RE. Symptoms of toxicity include:

• dry, itchy skin
• headache
• fatigue
• hair loss
• loss of appetite
• vomiting
• bone and muscle pain
• liver damage

Vitamin A toxicity can cause severe birth defects. If you are woman of childbearing age, limit your intake from dietary sources and supplements combined to no more than 1,600 RE.

Major Food Sources

The following foods contain carotenoids, which the body converts into vitamin A.

Antioxidant Capabilities
Free radicals are normal by-products of metabolism, but they can cause chain reactions that result in significant cell destruction. This cell destruction can, in turn, increase the risk for chronic diseases, including certain forms of cancer. Antioxidants have the ability to stop this chain reaction. The carotenoids, specifically lycopene, beta-carotene, and lutein, function in the body as antioxidants. Because of this antioxidant capability, carotenoids are being studied for a possible role in chronic disease prevention.

Tips for Increasing Your Vitamin A Intake
To help increase your intake of vitamin A:

• Pack cut carrots in your lunch for an afternoon snack.
• Slice a peach, mango, or apricot on to your breakfast cereal or oatmeal.
• Substitute a sweet potato for your baked potato. Just poke holes in the sweet potato and cook at 350 degrees for about 45 minutes to an hour (or microwave for six to eight minutes).
• Eat fruits and vegetables raw whenever possible. Vitamin A can be lost during preparation and cooking.
• Steam vegetables, and braise, bake, or broil meat instead of frying. This will help retain some of the vitamin content.