What are Free Radicals ?

[immerlustig]

hi

have recently read something about free radicals. if anyone could tell me what that is all about i´d be really happy.

i don´t mind eating fruit anyways but in connection with those radicals it might get a different meaning.

thanx in advance

roland

[Mr Black]

Free radicals are atoms or groups of atoms with an odd (unpaired) number of electrons and can be formed when oxygen interacts with certain molecules. Once formed these highly reactive radicals can start a chain reaction, like dominoes. Their chief danger comes from the damage they can do when they react with important cellular components such as DNA, or the cell membrane. Cells may function poorly or die if this occurs. To prevent free radical damage the body has a defense system of antioxidants.

Antioxidants are molecules which can safely interact with free radicals and terminate the chain reaction before vital molecules are damaged. Although there are several enzyme systems within the body that scavenge free radicals, the principle micronutrient (vitamin) antioxidants are vitamin E, beta-carotene, and vitamin C. Additionally, selenium, a trace metal that is required for proper function of one of the body's antioxidant enzyme systems, is sometimes included in this category. The body cannot manufacture these micronutrients so they must be supplied in the diet.

Vitamin E : d-alpha tocopherol. A fat soluble vitamin present in nuts, seeds, vegetable and fish oils, whole grains (esp. wheat germ), fortified cereals, and apricots. Current recommended daily allowance (RDA) is 15 IU per day for men and 12 IU per day for women.

Vitamin C : Ascorbic acid is a water soluble vitamin present in citrus fruits and juices, green peppers, cabbage, spinach, broccoli, kale, cantaloupe, kiwi, and strawberries. The RDA is 60 mg per day. Intake above 2000 mg may be associated with adverse side effects in some individuals.

Beta-carotene is a precursor to vitamin A (retinol) and is present in liver, egg yolk, milk, butter, spinach, carrots, squash, broccoli, yams, tomato, cantaloupe, peaches, and grains. Because beta-carotene is converted to vitamin A by the body there is no set requirement. Instead the RDA is expressed as retinol equivalents (RE), to clarify the relationship. (NOTE: Vitamin A has no antioxidant properties and can be quite toxic when taken in excess.)

I know, a lot of reading but I hope this helps.

Cheers,

Tyler

[immerlustig]

cheers tyler

that´s very informative indeed.

some more questions though : when do those free radicals actually occur? and how do they form? are there any cases of freedivers needing hospitalisation?

looking forward to more enlightenment

roland

p.s. do you know of any links maybe?

[cjborgert]

when do those free radicals actually occur? and how do they form? are there any cases of freedivers needing hospitalisation?

Don't mean any rudeness by jumping in on Tyler's thread, but thought I might give his keyboard an opportunity to cool down.

Free radicals are normal by-products of metabolism, so as long as you are alive, they are forming in your body. The liver, the lung - any organ that is metabolically very active - will form a large quantity of free radicals. But as Tyler has pointed out, our bodies have defense mechanisms that sop up free radicals before they cause too much damage. And then we also have repair mechanisms that repair damaged DNA and replace damaged proteins, etc.

A number of different lifestyle and environmental factors can increase free radical production. Excessive alcohol, smoking, drugs, chemical exposures, even breathing pure oxygen, increases free radical production and the chance that one's bodily defense will be overwhelmed.

Of course, a diet that is balanced and provides a complete complement of vitamins, and a lifestyle that avoids exposures that introduce even more free-radical damage helps our bodies maintain the edge against free radical damage.

[Mr Black]

Thanx CJ, you saved me some typing.

Cheers,

Tyler