Oxidative Stress: Meaning, Causes, Effects & Prevention

Life today exposes the human body to many different internal and external factors, which produce stress on individual cells within the human body. The main factor causing oxidative stress (or cellular damage) is free radical saturation, which occurs when the amount of free radicals overwhelms the number of antioxidants available and is able to counterbalance their effects.

Oxidative stress takes place when there is an imbalance between the number of free radicals and antioxidants the body has. Although free radicals are a by-product of natural metabolic reactions and serve a purpose within the metabolism of the body, when there is a surplus of them (greater than the amount that can be neutralized by antioxidants), free radicals are capable of causing damage to cells, DNA, protein, fat and cholesterol. Antioxidants serve as the body's first line of defense against free radical damage. When the levels of antioxidants in the body drop significantly, the cellular stress and fat damage will increase significantly.

Oxidative stress has been linked to the acceleration of the aging process, hormone imbalance, chronic inflammation, skin damage, weakened immune system, cardiovascular problems, and neurodegenerative diseases. The sooner the body is aware of oxidative stress, the easier it will be for an individual to begin making changes in their lifestyle that will promote long-term health.

There are multiple sources of oxidative stress. Environmental triggers, lifestyle choices, and biological processes all contribute to oxidative stress.

Environmental Oxidative stress is primarily caused by the effects of our environment on the body. Many environmental substances (e.g., air pollutants, industrial chemicals, cigarette smoke, vehicle emissions and hazardous gases) result in increased production of free radicals in the body.

The oxidative load created by these types of exposures increases with the use of pesticides, cleaning supplies and chemical agents (including many household items), as well as metal-based additives such as mercury and lead. Sunlight and ultraviolet radiation (UV) damage cells in the skin, leading to premature aging. It also creates free radicals.

Even inside our homes, things like inadequate ventilation, synthetic fragrances and indoor pollution build up daily and increase free radicals.

Some of the everyday lifestyle choices we make that can influence oxidative stress levels can be affected by our diet, exercise levels, and stress levels. Diets that are high in refined carbohydrates, sugar, fried foods and processed snack foods cause inflammation, creating the production of free radicals. Having a sedentary lifestyle leads to a lower metabolic rate, while participating in very high-intensity bouts of exercise without sufficient recovery periods will lead to an acute increase in oxidative stress. Chronic levels of stress and disrupted sleeping patterns cause high cortisol levels, which stimulate the formation of free radicals. Smoking and excessive alcohol consumption significantly reduce the effectiveness of antioxidants in our bodies.

There are many ways biological processes are involved in oxidative processes. When a cell generates energy, the mitochondria within that cell will naturally produce free radicals as a by-product of energy production. Additionally, when your body sends out a response to an infection or injury (metabolic) or when your immune system is producing an immune response to kill off pathogens, it will also produce free radicals to fight off those pathogens.

When oxidative stress affects the human body, it will accelerate the natural aging processes. Free radicals cause damage to the collagen & elastin and cells of the body that leads to wrinkles, fine lines & a dry appearance to the skin, as well as accelerated aging of the internal organs.

As stated previously, free radicals stimulate the inflammatory process throughout the body. Over time, that chronic low-grade inflammation leads to arthritis, metabolic disorder, autoimmune disorder & heart disease.

The free radicals created through oxidative stress attack the membranes of the cell and the DNA, which leads to mutations and weakened tissues' ability to repair themselves. This "defect" in a cell's ability to repair itself can raise the risk of developing cancer, slow down the healing process, and lower the lifespan of the cells.

Once again, oxidative stress has a very negative effect on the body and endothelial cells. Oxidative stress can oxidize the LDL cholesterol as well as cause hardening of the arteries, which increases the amount of plaque build-up and in turn, decreases circulation and increases the chances of developing high blood pressure and heart disease as well as the likelihood of stroke.

Brain is one of the most sensitive organs in relation to oxidative damage. The long-term, progressive impact of oxidative stress creates impairments in memory, decreases cognition, and causes disorders, such as Alzheimer's Disease and Parkinson's Disease.

Several factors increase susceptibility to oxidative stress, including:

• Chronic conditions like diabetes, PCOS, hypertension, obesity, and autoimmune disorders

• Diets low in fruits, vegetables, and essential vitamins

• High intake of sugar, processed foods, and fried items

• Smoking or passive smoke exposure

• Poor sleep quality

• Chronic emotional stress

• Excessive alcohol intake

• Exposure to pollution, chemicals, and pesticides

• Vitamin deficiencies (especially vitamin C, E, zinc, and selenium)

Recognizing these types of risk factors may enable a person to develop an early preventive plan of attack.

Reducing oxidative stress is entirely achievable with consistent lifestyle changes, balanced nutrition, and mindful habits.

Food is the strongest defense against oxidative stress. A diet rich in antioxidants supports cell repair, reduces inflammation, and neutralizes free radicals. Some excellent choices include:

• Berries

• Leafy greens

• Tomatoes

• Nuts and seeds

• Green tea

• Turmeric

• Olive oil

• Avocados

Avoiding a high amount of sugar, processed foods, trans fats, and/or refined carbohydrates will greatly decrease the emergency chemical cell stress level.

Living a consistent daily lifestyle will strengthen the body’s ability to make its own antioxidants. Regular physical activity at moderate levels will help to increase blood flow, resulting in higher levels of antioxidant enzymes; chronic stress reduction techniques (e.g., meditation, yoga, deep breathing, and walking in nature) reduce cortisol levels; and quitting smoking and limiting alcohol consumption can reduce the amount of oxidative stress on the body.

In situations where diet does not provide enough antioxidant support, supplementation may be warranted. Popular examples of antioxidant supplementation include:

• Vitamin C

• Vitamin E

• Coenzyme Q10 (CoQ10)

• Curcumin

• Resveratrol

• Omega-3 fatty acids

• Green tea extract

Use these supplements carefully and, if possible, discuss any potential side effects with a healthcare professional.

Adequate water intake allows the body to effectively eliminate toxins and promote cell repair and healing. Being adequately hydrated allows for the efficient transportation of nutrients to the cells and the efficient removal of toxins, thereby minimizing oxidative stress on the cells.

Small changes can result in significant reductions in the amount of toxins we are exposed to, such as using natural cleaning products, reducing the use of plastics, ensuring adequate ventilation in our indoor spaces, purchasing organic produce at the market, and reducing the number of chemical-based sprays we use for pest control.

Excess body fat can create an inflammatory response in the body, which can result in increased oxidative stress. A balanced diet coupled with regular exercise can help maintain body weight at a healthy level, support the body’s metabolism, and decrease the amount of free radicals present in the body.

The body repairs and heals cells during sleep, and it produces its own antioxidants. Maintaining a regular sleep schedule, reducing screen time, and providing a cool and dark environment for sleeping will all enhance the body’s ability to obtain restorative sleep and sufficient time for healing and cellular repair.

Since they produce large amounts of free radicals when you spend time in the sun all day long, it is important to protect your skin by wearing sunscreen, covering it with clothes (if necessary), and using skin care products containing antioxidants.

Blueberries, strawberries, raspberries, and blackberries are packed with anthocyanins (this is a type of antioxidant that helps protect your cells) and help maintain healthy aging.

Leafy greens such as spinach, Swiss chard, and kale all of these provide vitamins A, C, and K as well as phytonutrients to help support your skin's antioxidant defenses.

Walnuts, almonds, sunflower seeds, chia seeds, and flaxseeds contain Vitamin E and Omega-3 fatty acids, which both have anti-inflammatory and antioxidant properties.

Green tea contains antioxidants (EGCG) that help lower inflammation and support the body's metabolic process.

Contains curcumin, which is an antioxidant and a strong anti-inflammatory agent.

High-quality dark chocolate (70% or more cocoa) contains flavonoids that boost blood flow and help protect against oxidative damage.

The main cause of oxidative stress is the accumulation of free radicals. Free radicals are produced as by-products of normal metabolism and exposure to environmental toxins. 

Oxidative stress affects the body's immune system and contributes to many age-related diseases. The good news is that we can take steps to reduce our oxidative stress levels. We can help protect our cells and improve our health by understanding what causes oxidative stress to occur and how it impacts the body. 

There are many simple actions we can take, such as eating a diet high in antioxidants, reducing stress levels, exercising regularly, sleeping well, and avoiding exposure to environmental toxins. Taking these steps will greatly reduce the amount of damage to our cells caused by free radicals. Although some dietary supplements may help with this, the most effective means of combating oxidative stress is through a healthy, well-balanced lifestyle that includes eating a diet rich in antioxidants, engaging in regular physical activity, managing stress effectively, and sleeping well. 

Overall, making these lifestyle changes not only decreases oxidative stress but also enhances immunity, increases energy, promotes healthy skin, and establishes a foundation for a healthy and long-term future.