Archive for the ‘vitamin A’ Category

Alphabet Soup starting with Vitamin A

Friday, December 5th, 2008

Some of you have asked about vitamin supplements and which ones are most important. The answer is simple: all of them, and the phytonutrients and everything else that comes with your food. (Don’t believe the old dictionary definition of phytonutrient, which says it is a non-essential bioactive plant substance, such as a flavonoid, considered to have health benefits.) [This shows even dictionaries get out of date.]

I will take a series of days to go through the alphabet with you, so if you know all about the vitamins just skip the next couple of days.

Vitamin A

This vitamin was one of the first to be discovered. It keeps your eyesight keen, your skin healthy, and your immune system strong. So it is no surprise that an extra dose may help treat various eye problems, a number of skin disorders and a wide range of infections.

Vitamin A is a fat-soluble nutrient which is stored in the liver. The body gets part of vitamin A from animal fats and makes part in the intestine from beta-carotene and other carotenoids in fruits and vegetables. It is present in the body in various chemical forms called retinoids, so named because the vitamin is essential to the health of the retina of the eye.

Vitamin A is probably best known for its ability to maintain vision, especially night vision. It also strengthens resistance to infection.

Vitamin A was first used in the 1940s to treat skin disorders, including acne and psoriasis, but the doses were high and toxic. Today the recommended daily allowance is 2,300 IU for women over 19 and 3,000 for men over 19. There is a danger for taking too much vitamin A although there is some debate over how much is too much.

Vitamin A supplements should be taken with food and a little fat in the diet helps with absorption. Also vitamin E and zinc help the body use vitamin A.

Vitamin A is also found in fish, egg yolks, butter, organ meats such as liver (3 oz provide more than 9,000 IU). Fortified milk, dark green, yellow, orange, and red fruits and vegetables have large amounts of beta-carotene and many other carotenoids, which the body makes into vitamin A on an as-needed basis.

BETA-CAROTENE was once considered a potent source of vitamin A. And today it has gained importance as a disease-fighting substance. Beta-carotene along with a number of related nutrients called carotenoids, may protect against illnesses as heart disease and cancer.

Beta-carotene is an antioxidant which has reversed some precancerous conditions.

It’s almost impossible to get too much beta-carotene. The body discards what beta-carotene it doesn’t process. It you get more than 100,000 IU a day for and extended period your palms and soles may get an orange tone, which disappears when you lower the dose.

Carrots are a rich source of beta-carotene as well as other yellow, orange, and red fruits and vegetables. The darker the green vegetable the more beta-carotene.

For further study: Guide to Drugs and Supplements, 2007