The skin and its appearance are the first characteristics that "reflect" our age, and we say reflect in quotes because often its appearance does not correspond to the actual age. Some people have skin that makes them look 10 years younger, but unfortunately, it is more common for their appearance to make them look up to 20 years older than they really are. In these cases, the skin has aged faster than the rest of the body…
Why the skin ages prematurely
This premature aging of the skin is caused by oxidative stress, (Oxidative Stress: myth or reality) which leads to a decrease in the production of collagen, elastin, and hyaluronic acid, the substances that give the skin its firmness, hydration, and elasticity. The disappearance of these factors is summarized in one sign… the appearance of wrinkles.
What is oxidative stress
Oxidative stress is a condition in which oxidizing substances such as free radicals and ROS (reactive oxygen species) prevail over antioxidant substances, (What are antioxidants in simple words) which would have the capacity to neutralize them. Oxidizing agents are capable of damaging biomolecules (biological molecules) such as lipids, proteins, and DNA. This accumulated damage will lead to a progressive malfunction of cells, tissues, and organs, causing the appearance of diseases and aging itself.
Why the skin is at greater risk of oxidative stress
Oxidative stress is a condition that can affect all organs of the body, but in one of the places where it is more evident, is the skin. If we compare the skin of two people of the same race, similar age, but one of them lives in a monastery, and the other is constantly exposed to the sun (because they are a fisherman), we will see that the first has smoother, firmer, and more elastic skin; while we will find the opposite in the second. What we will be observing in the skin of the fisherman is the result of his chronic exposure to higher oxidative stress. The skin is an organ very susceptible to the action of free radicals; it is especially at risk for several reasons:
- It is exposed to oxygen in two ways: from its inner side through the blood, and on its surface to the oxygen contained in the air.
- It is exposed to ultraviolet light, which generates free radicals.
- It is rich in fatty acids, making it highly susceptible to lipid oxidation reactions.
Oxidative stress in the skin, beyond aesthetics
Aging and the appearance of wrinkles and dryness are the aesthetic part of the problem caused by oxidative stress in the skin, but free radicals are also involved in the pathogenesis of many dermatological diseases; either as the etiological agents generating them or as part of the dermatological disease process. The sun has an obvious and significant contact with the skin. Ultraviolet light causes the formation of free radicals in skin cells, which depending on the dose, those free radicals can exceed the skin's antioxidant defenses, causing damage to cellular proteins, lipids, and DNA, ultimately leading to the appearance of pathologies. Three clinical manifestations of sun damage can be attributed, in part, to the production of free radicals: Photoaging, which is qualitatively and quantitatively different from chronological aging. It is caused by deficient antioxidant action against the cumulative stress produced by free radicals, originating from repeated and chronic sun exposure, which induces structural and functional alteration of skin components. Skin cancer. Free radicals are particularly related to the generation of cancer, as they can cause DNA damage by two mechanisms: the first by the binding of oxidizing substances generated (by UV radiation) to DNA, and the second by the oxidation of membrane lipids, which leads to an increase in intracellular calcium, leading to the activation of certain enzymes within the cell nucleus. Either mechanism will result in DNA mutations and breaks that lead to cancer. Photodermatoses. Some diseases such as drug-induced photosensitivity have been related to free radicals, as clinical symptoms have been shown to be reduced with the use of antioxidants.
How to prevent aging and other skin alterations
Oxidative stress damage occurs throughout the body, but as we have seen, in the skin it is notoriously intense, affecting both functional and aesthetic aspects. Protecting the skin against oxidative damage is possible. We must consider the skin as an organ with two surfaces: one in direct contact with oxygen and ionizing radiations such as UV rays from the sun; and another in direct contact with our internal environment, starting with the subcutaneous tissue. Therefore, the skin care strategy should consider both external and internal protection. For external protection, we would use:
- Sunscreens, carefully selected taking into account the sun protection factor (SPF) of the product, which represents the number of times the photoprotector increases the skin's natural defense capacity against erythema or redness prior to burning.
- Antioxidant creams. There are antioxidant creams on the market that, although they can help, we must remember that ultraviolet rays also reach the deeper layers of the skin, and due to their physicochemical characteristics, external antioxidants do not penetrate that far.
