By Clark Bailey, Owner of Bailey's Health Store
Vitamin A was the first vitamin to be discovered being identified in 1913 by two American scientists. It wasn't until 1930 that the structure of vitamin A was determined. In 1935, vitamin A was found to be necessary for normal vision. In the 75 years since, there has been a great deal of research into the role vitamin A plays in growth, development and reproduction.What is vitamin A?
There are many sources of vitamin A, however, it is generally divided into two main types. The first type is pre-formed vitamin A which is often found in the form of retinol or retinal. This form is found in animal products such as liver, butter, whole milk (added) and egg yolks. The second type is provitamin A and is found in plant pigments known as carotenes (or carotenoids). Of these, beta carotene is the best known. Provitamin A compounds are turned into vitamin A in the body.
Both types of vitamin A are fat soluble meaning that it is absorbed and retained in the body unlike non-soluble vitamins that are passed through the body without being absorbed. Excessive intake of vitamin A may cause problems such as headaches; bone and joint pain; dry, itchy skin and liver damage. Pregnant women taking daily doses above about 10,000 IU (3,000 mcg RE) may also cause birth deformities.
How Does Vitamin A Benefit the Body?
Vitamin A is important to growth, repair and cell differentiation including bones, teeth, collagen and cartilage. It also helps to modify unspecialized cells so they can perform specific functions (cell differentiation) playing a central role in tissue development and maintenance. Because of its role in cell development and differentiation, it is believed that adequate amounts of vitamin A are beneficial to fetal development during pregnancy.
Vitamin
A plays a vital role in the formation of healthy epithelial cells which cover the internal and external surfaces of the body. These cells are found in the skin, lungs, inner ear, cornea, sex organs, glands, gland ducts, gums, nose, cervix and developing teeth.Vitamin A is essential for protection against infection. It is known as the "anti-infective vitamin" because of its role in protecting the body from infection. It does this by helping the body surfaces perform as barriers against invading micro-organisms. It also enhances immune functions such as antibody responses and the activity of various white blood cells. Laboratory experiments have found vitamin A to have antiviral and antioxidant activity thus playing a role in protecting against free radical damage that contributes to many common diseases.
Vitamin A is believed to be essential for healthy eyes and vision as it is involved in production of a chemical called visual purple. Visual purple improves the ability to see in dim light. It also helps protect against xerophthalmia, a condition of severely dry eyes, formation of ulcers on the cornea, swollen or sticky eyelids and, eventually, blindness.
Am I Getting Enough Vitamin A?
Symptoms of deficiency of this essential vitamin include night blindness, xerophthalmia (severe eye condition), dry skin, retarded growth, increased susceptibility to infection and cancer. The World Health Organization estimates that as many as 250 million children worldwide suffer from vitamin A deficiency although it is less common in advanced countries.
Intake of vitamin A supplements (within daily recommended limits) is believed to boost immunity; help prevent cancer; treat skin disorders such as acne and psoriasis and treat eye problems. Vitamin A supplements should not be combined with vitamin A-derivative acne medication or broad spectrum antibiotics. While there are many benefits to taking vitamin A supplements, the preferred consumption method is through improved diet. There are times when supplements are needed to achieve the recommended daily intake of vitamin A. We offer a wide selection of high-quality products for daily vitamin A intake as individual vitamins or as part of a multi
-vitamin regimen. The recommended dietary allowance (RDA) for men is 3,333 IU per day. For women, it is 2,666 per day. These values are based on the amount needed to prevent the eye disease xerophthalmia with an added margin of safety. Pregnant and lactating women should follow the advice of their physician.
These products are not intended to diagnose, treat, cure or prevent any disease. Always consult your physician or licensed medical provider about these or any other nutritional products before taking them.
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