Oxidative stress occurs when some molecules (oxidizing agents) take electrons from other molecules or atoms. The substances that can exist with missing electrons are called free radicals. Most of these free radicals are oxygen molecules or atoms. 

Free radicals are highly reactive, always ready to give away the odd electron, or to accept one. After they find a pair for the lonesome electron, they loose their activity, but the atom that has just lost an electron becomes a free radical in turn. It is a necessary part of metabolic process. However, too many free radicals cause a dangerous chain reaction that destroys cellular compounds and can damage DNA, proteins and lipids (fats). 

Cellular damage can result in diseases, such as cancer, inhibit enzyme activity and produce mutations in genetic material that makes aging go faster. 

How exactly can oxidative stress speed skin aging? 

Wrinkles occur when skin loses its elasticity. The loss of elasticity is caused by extensive formation and accumulation of collagen cross-links. Collagen cross-linking is a result of a chemical process that starts with nonenzymatic attachment of glucose to a collagen molecule. 

When enzymes attach glucose to collagen, there is a reason for it and a purpose. Nonezymatic attachment, on the other hand, is random. Collagen cross linking in this case is uncontrollable and more often than not - unnecessary. 
Once cross-linking occurs, it is irreversible. 

Enzymes are produced by our bodies, but with the course of time the number of produced  enzymes declines. Besides irreversible processes in the body, other factors can inhibit enzyme production. Namely - free radicals. 

As mentioned earlier, free radicals have a negative effect on enzyme activity. Free radicals appear as a result of metabolism.  Another factor is the UV exposure. Metabolism is a part of life, and free radicals will appear no matter what. But their harmful activity can be countered by the vitamin intake (vitamins E, C, carotenes and flavonoids). Sun damage can be significantly reduced, if not totally prevented, by the use of the right skin care products that contain antioxidants. 

These elements - antioxidants - become an easy target for free radicals. They don't turn into free radicals themselves. They catch free radicals and bond with them. As soon as a free radical is bonded with an antioxidant molecule, it loses its activity and is no longer dangerous. 

Natalie Katsman 
Aloe and Vitamin C for the skin. 
http://www.natural-aid.com 
The latest in anti-aging technology. 
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