Vitamin A - Aiding Cellular Health

Epithelial are one of four tissue types found in the body. Epithelial cells help to protect or enclose organs; some produce mucus or other secretions. Certain types of epithelial cells have tiny hairs called cilia, which help remove foreign substances.

The epithelial cells cover the internal and external surfaces of the body and are found in:

• Skin
• Lungs
• Developing teeth
• Inner ear
• Cornea of the eye
• Sex organs
• Glands and their ducts
• Gums
• Nose
• Cervix
• Other areas

Vitamin A is essential in the formation of healthy epithelial cells and in keeping the mucous membranes, which line all the cavities of the body, in healthy condition. The mucous produced by epithelial cells is necessary to lubricate body surfaces and protect against invading micro-organisms. For example, the maintenance of the vaginal lining and uterus is important in fertility, and the health of the digestive tract lining is important in protecting against ulcers.

The mucous membrane has two layers:

1. The top layer, known as epithelium. It is composed of billions of cells.
2. The mucous membrane lies close under the epithelium. It is a thin layer of involuntary muscle fibers, which are extremely pliable and elastic.

The vitality of this lining is dependent upon an adequate supply of vitamin A. Should a vitamin A deficiency occur, the cells harden and degenerate into a rough, horny surface. This would obstruct the normal secretory function, resulting in infection. These infections could affect the bladder, kidneys, mouth, tonsils, sinuses, tongue, ear canal, eyes, or tear ducts.

Many studies have shown that vitamin A deficiency is associated with increased risk of infection in developing countries. However, this may also be the case in developed countries. For example, a study in 1992 involving 20 children with measles in Long Beach, California found that half of them were vitamin A deficient.

Vitamin A deficiency adversely affects the epithelial surfaces, causing increased susceptibility to skin and respiratory infections. Antibody functions and immune cells are also affected, which may lead to an increase in pre-cancerous cells in the epithelial tissues of the lungs, mouth and throat.

There are many sources for vitamin A. The richest sources of ready-made vitamin A are beef liver, milk and milk products, butter, eggs, and fish liver oils. Our body is also capable of producing vitamin A from carotenoids found in foods such as carrots, sweet potatoes, pumpkin, turnip greens, and even romaine lettuce.

Eating a well balanced diet should provide you with the vitamin A that your body so desperately needs. If you suffer from a chronic health condition which may compromise your vitamin absorption, consult your doctor for advice on supplementing your diet.