After decades of research, the free radical theory is the most prominent and recognized theory of why and how we age. Free radicals have a major impact on not only the health and youth of the skin but on the whole body.
An understanding of the impact of free radicals on our skin and the aging process is essential for the aesthetic professional. Let’s dive deeper into the free radical theory and how we can help our clients remain healthy through the years.
What are the Theories of Aging?
At present, there is no single explanation for why we age. In fact, there are up to 30 different evidence-based theories on aging that are currently accepted by the National Institutes of Health. Some of the best theories include the free radical model, inflammation model, glycation model, DNA/genetics/epigenetics model, and mitochondrial aging model.
Of these, the most widely accepted model is the free radical and oxidative stress theory.
What is the Free Radical Theory?
The free radical theory of aging originated in the 1950s. Dr. Denham Harman postulated that free radicals damage cells, leading to further ongoing damage and functional issues. Over time, this cellular damage accumulates into tissue, organ, and eventually full system damage that causes aging and eventual death.
Today, the free radical theory of aging still holds that free radicals largely contribute to the body’s aging processes and general decline. In the aesthetics world, free radical damage plays a significant role in skin health, especially concerning photoaging.
What are Free Radicals?
Free radicals are high-energy molecules with an unpaired electron in their outer orbit. This unpaired electron makes the molecule imbalanced and particularly volatile as it seeks to pair up with another electron. The free radical will steal an electron from anything it encounters to complete its outer orbit. This is called oxidation, and as it occurs, the free radical damages a healthy structure and then leaves it with an unpaired electron. The cycle continues, leaving more and more damaged cells and tissues along the way.
How Do Free Radicals Affect the Skin?
As our outer defense network, the skin is subject to high levels of stress and damage. When it comes to free radicals, the skin is targeted by both internal cellular metabolism and outer environmental factors like sun exposure.
Free Radicals from Internal Cellular Metabolism
Energy is produced within our cells by metabolic processes using the nutrition in our food. All cells need energy to function and fill our energy reserves. The skin uses energy to make collagen, elastin, and a functional barrier to promote health.
To generate the energy required for these functions, free radicals are created. While this energy production is necessary for life – and healthy skin – it also causes gradual damage and decreases the physiologic reserve, leading to aging. The constant process of making and storing energy leads to an ongoing cycle of oxidative stress. In most areas of the body (not the skin), 85% of free radical damage results from the necessary process of cellular metabolism.
Free Radicals from External Sun Exposure
The skin experiences the same free radical damage from cellular metabolism, but unlike any other tissue of the body, it is also subject to ongoing damage from sun exposure.
Sunlight is damaging to our skin mainly because of its tiny energy packets called photons. Photons are responsible for up to 85% of the skin’s free radical damage. This damage accumulates over time and leads to the gradual decline of cells and tissues and eventually aging.
Other Sources of Free Radical Damage
Pollution: In addition to sun exposure, other environmental factors cause free radical damage. Poor air quality is a major contributing issue to damaged skin, lung health, and other health issues. Pollution contains particularly toxic elements like ozone, nitrogen dioxide, and sulfur dioxide. Pollution also contains “particulates”, small particles of dust or debris plus highly damaging soluble metals and polycyclic aromatic hydrocarbons. Sadly, most of the world lives in areas with poor air quality. As a result, these people are subject to faster aging, inflammation, and skin diseases.
Smoking: Cigarettes and other tobacco products cause extreme amounts of free radical damage to both the skin and internal organs. Tar, particulates, and other toxins in cigarette smoke wreak havoc on the lungs and skin and lead to cardiovascular and respiratory diseases.
Protecting Against Oxidative Stress and Aging: Antioxidants
Free radical damage seems to be everywhere, but nature does provide us with some protection against overwhelming oxidative stress, mainly in the form of protective enzymatic antioxidants:
- Superoxide Dismutase
- Glutathione Peroxidase
While these enzymes help protect against some damage, they cannot prevent free radical damage entirely. As we age, oxidative damage occurs faster than these enzymes can correct.
Additional antioxidants are needed to supplement the actions of the above enzymes and neutralize free radicals. Antioxidants target and bind with free radicals, sacrificing an electron to them and breaking the cycle of damage.
Antioxidants are found in healthy food sources, but typically only 1% of these dietary antioxidants reach the skin surface. Thankfully, antioxidants can be used topically. Many cosmeceutical products use antioxidants to revitalize and protect the skin against free radical damage.
A Healthy Lifestyle to Prevent Free Radical Damage
Free radicals may be impossible to escape, but there are many ways we can protect our skin against their damaging effects. Clients looking for healthier skin should be advised to use sunscreen, eat a diet rich in antioxidants, and avoid smoking and polluted areas. Using quality topical antioxidant products will enhance the network of skin protection.