Fighting Free Radicals with Antioxidants

Allison Sayre, WHNP

Understanding Free Radical Chemistry

Central to the complexity of the human body, there is a network of millions of biochemical reactions that occur every second to keep us alive and functioning. Within this network, there is a constant push and pull between forces that promote health and those that can undermine it.

Among the more potentially “harmful” agents within our bodies are free radicals. These unstable molecules are natural byproducts of normal metabolic processes, but when left unchecked, they can contribute to dysregulated immune response, premature aging, and disease. Fortunately, our bodies are not defenseless. We have antioxidants. Antioxidants, and nutrients with antioxidant activities, are the molecules that neutralize these free radical threats and help maintain cellular balance.

In this article, we’ll provide a deeper explanation of what free radicals and antioxidants are, how they’re formed, why they matter, and how antioxidant activities balance the damaging effects of free radicals. With a foundational understanding of free radical chemistry, we can better understand why supporting antioxidant defense is essential for long-term health and vitality.

What Are Free Radicals?

Free radicals are atoms or molecules that contain an unpaired electron in their outer shell. This unpaired electron makes the molecule highly reactive and unstable. Most free radicals in the human body are derived from oxygen, and these are referred to as reactive oxygen species (ROS). Specifically, it is the oxidative phosphorylation that takes place in mitochondria that is responsible for 90% of ROS generation. ROS produced by mitochondria include superoxide ions, which can be converted to hydroxyl ions and hydrogen peroxide. [1]

Electrons like to exist in pairs, and a molecule with an unpaired electron will seek out other electrons to stabilize itself. This “electron scavenging” behavior leads to a chain reaction in which the free radical steals an electron from a neighboring molecule. Electrons are often stolen from lipids, proteins, or DNA, causing that molecule to become a free radical itself. This domino effect can result in significant damage to cellular structures, apoptosis, or mutagenesis, through a process referred to as oxidative stress. [2]

How Free Radicals Form in the Body

The generation of free radicals in the body is not however, entirely bad. In fact, it is an essential part of many physiological processes. For example, immune cells produce free radicals to destroy invading pathogens. However, problems arise when the ratio of free radical production and antioxidant repair becomes imbalanced.

Free radicals in the body can be generated from:

• Normal metabolic activity: The process of converting food into energy in the mitochondria creates reactive oxygen species as a byproduct. [1]
• Imbalanced cytokine activity: Immune responses, especially chronic ones, increase ROS production. [2]
• Environmental exposure: Pollution, smoking, pesticides, and industrial chemicals can all increase the generation of free radicals. [2][3]
• Ultraviolet light: UV rays from the sun can stimulate free radical production, mutagenesis, and signs of premature aging in skin cells. [4]
• Alcohol and certain drugs: These can stress liver detoxification systems and promote ROS formation. [5]

Over time, chronic exposure to high levels of free radicals can damage tissues, impair cellular function, and contribute to the development of specific health conditions and premature aging. [1-5]

What Are Antioxidants?

Antioxidants, and nutrients with antioxidant activities, are molecules that can safely donate an electron to a free radical, thereby neutralizing it and preventing further oxidative damage. Unlike the free radicals they quench, antioxidants remain stable after losing an electron. This unique property makes them vital to the maintenance of biological homeostasis.

Antioxidants can be enzymatic or non-enzymatic:

• Enzymatic antioxidants include compounds like superoxide dismutase (SOD), catalase, and glutathione peroxidase. These are produced within the body and work as part of complex biochemical pathways to neutralize free radicals. [6]
• Non-enzymatic antioxidants (and nutrients with antioxidant activities) include vitamins (such as vitamin C and vitamin E), polyphenols, flavonoids, carotenoids, and other phytochemicals commonly found in fruits, vegetables, and other plant-based foods. [6]
• Together, these compounds create a powerful defense system that can limit the chain reaction caused by free radical damage.
  How Antioxidants Scavenge and Neutralize Free Radicals
  Antioxidants protect cells through a process called scavenging. When a free radical encounters an antioxidant, the antioxidant donates an electron to the radical, stabilizing it without becoming a reactive molecule itself. This effectively stops the chain reaction of damage. 

Different antioxidants have affinities for different types of radicals. For instance, carotenoids are particularly effective against lipid peroxidation (damage to fat-containing structures like cell membranes), while vitamin C is water-soluble and works in aqueous environments like the bloodstream. [6]

Balancing Free Radicals and Antioxidants

When free radicals overwhelm our antioxidant defenses, oxidative stress ensues. However, the complete elimination of free radicals is not a goal to strive for. After all, some are necessary for signaling and immune function. A healthy balance, known as redox homeostasis, happens when antioxidant defenses are sufficient to counteract the number of free radicals produced, and the body is in a state of equilibrium. [7]

Several lifestyle factors support this balance:

• Diet: A diet rich in colorful fruits, vegetables, herbs, and whole foods provides a wide range of antioxidants. [6]
• Exercise: Moderate exercise improves antioxidant enzyme systems, while overtraining can increase oxidative stress. [8]
• Sleep: Quality rest at regular intervals supports cellular repair and antioxidant capacity. [8]
• Avoiding toxins: Limiting exposure to pollutants, smoke, and processed foods reduces external influences on free radical generation. [3][9]
• Stress management: Chronic psychological stress can also increase oxidative activity in the body. [8]

Conclusion: Guarding Against Oxidative Stress

Understanding free radicals and antioxidants is a window into how the body maintains its intricate balance through daily function. While free radicals in the body are a natural and sometimes necessary occurrence, the danger lies in their excess and the damage they can inflict on vital tissues when left unchecked.
Antioxidants, and nutrients with antioxidant activity, serve as our biochemical neutralizers, halting the chain reactions of oxidative damage and preserving cellular health. They are essential allies in the fight against premature aging, disease, and the wear and tear of daily life.

By prioritizing antioxidant-rich diets, minimizing environmental exposures, and supporting the body’s natural defenses, we can take meaningful steps toward maintaining that delicate yet crucial balance between free radical chemistry and the protective role of antioxidants.

Disclaimer:
The information provided is for educational purposes only. Consult your physician or healthcare practitioner if you have specific questions before instituting any changes in your daily lifestyle including changes in diet, exercise, and supplement use.

Allison Sayre, MSN, WHNP specializes in women's health and functional medicine, blending both traditional and integrative approaches. With over 18 years of experience, she has empowered women to reclaim their health through personalized nutrition and supplementation, hormone balancing, and lifestyle modifications. 
She received her Bachelor of Science from Mount Carmel College of Nursing and her Master of Science from the University of Cincinnati. She has been a certified women’s health nurse practitioner since 2014 and has continued her education and training in functional medicine from both the Institute for Functional Medicine as well as the American Academy of Anti-Aging Medicine.