Scientists now believe that the free radical theory of disease also applies to the aging of the skin. Free radicals are unstable small molecules generated by an oxygen environment which require stabilization by the body's antioxidant system.  Free radicals occur throughout every cell in our body simply by virtue of the fact that oxygen is our principal metabolic fuel.  Strong sunlight readily generates free radicals in the skin.  Our hands, face, neck, and arms are the areas usually chronically exposed to light.  These parts of the body, particularly the face, are where aging of the skin shows up.

The skin protein collagen is particularly susceptible to free radical damage, and when this damage occurs, it causes the collagen protein molecules to break down and then link back up again in a different way; this is known as cross-linking. Collagen cross-linking causes the normally mobile collagen to become stiff and less mobile. Sunlight also causes the messenger molecules present in skin cells to become active and create inflammatory products. Research shows that the multiple small exposures to ultraviolet irradiation lead to
sustained elevations of enzymes that degrade skin collagen and contribute to photo-aging.

Skin cancer typically occurs in skin that is photo-aged. Wrinkles, laxity, uneven pigmentation, brown spots, and a leathery appearance characterize photo-aged skin. In contrast, chronologically aged skin that has been protected from the sun is thin and has reduced elasticity, but is otherwise smooth and unblemished.

The following factors can accelerate skin aging:

• sun exposure
• first or secondhand cigarette smoke
• environmental toxins
• poor diet
• excess alcohol consumption
• stress
• harsh soaps or detergent-based moisturizers
• sleep deprivation

One way of mitigating the effects of these skin-damaging foes is to increase levels of protective antioxidants through a diet rich in fruits and vegetables or by direct topical application.

In a double-blind study, a topical vitamin C complex was applied to one half of the face and a placebo gel to the opposite side.  Clinical evaluation of wrinkling, pigmentation, inflammation, and hydration was performed prior to the study at weeks 4, 8, and 12. The results showed a statistically significant improvement of the vitamin C-treated side, with decreased photo-aging scores of the cheeks and the perioral area.

The peri-orbital area improved in both the vitamin C and placebo-gel group, probably indicating improved hydration. The overall facial improvement of the vitamin C side was statistically significant.  Biopsies showed increased collagen formation in the vitamin C group. This study showed that topically applied vitamin C results in clinically visible and statistically significant improvement in wrinkling when used for 12 weeks. This clinical improvement correlated with biopsy evidence of new collagen formation.

Other Factors
In spite of the effect of sunlight on the skin, there are other factors that affect skin health that occur regardless of our exposure to sun rays. Dryness, loss of tone and fullness, diminished immune responses, and reduced ability to repair damage are all factors that contribute to the aging process.

There are many types of skin tones and qualities. Men tend to have thicker skin than women due to the dominant hormone testosterone. However, in later years, the lack of estrogen in women and testosterone in men tend to cause changes in both genders.

Each individual will have a different skin, with different oil production, color, and texture. Clearly, people with dry, white skin should use only mild cleansers and never use grainy cleansing products. Moisturizers and oil-based make-ups will also be required.

On the other hand, those with an oily, darker skin can use mild liquid cleansers and an oil-blotting foundation. Generally, the use of sunscreens is reasonable as long as it does not create a false sense of security. Do not go out for longer periods of time in the sun just because you're wearing a sunscreen.

Skin damage occurs when the membrane covering of the skin cell is damaged by free radicals. Free radicals make the membrane more permeable, allowing the cells to dehydrate (lose water). The membrane of the cell is what is called a lipid bilayer: two layers of fat end-on-end. Enzymes are activated when the skin is traumatized or exposed to sun. Enzymes break down the lipid bilayer and cause inflammation. Thus, any antioxidants must be fat-soluble to protect this layer.

Chronic inflammation is an underlying cause of common degenerative diseases. One study found that pro-oxidative factors that accelerate skin aging might activate a self-maintained micro-inflammatory process that interferes with skin elasticity and thickness. This study stated that topical antioxidants decrease this inflammatory cascade and thus afford protection to the skin structures.

The effect of exposure to even ambient UV irradiation increases the risk for long-term, detrimental effects characterized by wrinkles and loss of skin tone and resilience. Photo-aged skin displays prominent alterations in the cellular component and the extracellular matrix of the connective tissue. UV exposure results in an accumulation of disorganized elastin and a severe loss of collagens, the major structural proteins of the dermal connective tissue.

The unifying pathogenic agents for these changes are UV-generated free radicals. As well as causing permanent gene mutations, free radicals activate signal transduction pathways that are related to growth, differentiation, senescence, and connective tissue degradation.

This is why its so important to drink lots of water throughout the day, eat fresh vegetables and fruits, get moderate amount of exercise, avoid smoke of any kind, moderate alcohol, laugh a lot, avoid toxic chemicals in your make-up, soaps, detergents, no more than 15 minutes of direct sun, and get that beauty sleep (don't sleep on your stomach: causes facial wrinkles and jaw problems).