Understanding and reducing oxidative stress

Oxidative stress occurs when there is an imbalance between the production of free radicals and the body’s ability to combat their harmful effects. Free radicals can damage cells and promote inflammation, which can lead to a wide range of health problems. But what exactly happens to us when we experience oxidative stress, and how does it work? Keep reading to learn more about oxidative stress and what you can do to reduce it, improve your overall health, and protect yourself from many chronic diseases. 

Table of Contents

• What is oxidative stress?
• What are free radicals and antioxidants?
• How does oxidative stress develop?
• Which diseases are caused by oxidative stress?
• How can oxidative stress be detected?
• What can I do about oxidative stress?
• Summary

What is oxidative stress?

Oxidative stress may sound like a complicated medical term, but to understand it, we only need to break down the two words. “Oxidative” refers to an oxidation process, while “stress” implies that this process places a burden on the body. In the context of oxidative stress, it means that there is an increase in the production of certain molecules known as “free radicals” and a decrease in the body’s ability to fight and neutralize them. When the body can’t effectively control the number of free radicals, these molecules can start causing damage by attacking other molecules in the body and “oxidizing” them. This can lead to a range of health problems, including chronic diseases and premature aging (Pizzino et al., 2017). 

What are free radicals and antioxidants?

Free radicals are molecules that have one or more unpaired electrons. An electron normally looks for a partner to pair with. However, since free radicals do not have partners for their unpaired electrons, they become unstable and highly reactive. They constantly seek other electrons to pair with and attack other molecules such as DNA, proteins, and lipids. This process can lead to cellular damage and dysfunction (Lobo et al., 2010). 

Antioxidants are natural substances found in our bodies and in food. They have the ability to neutralize free radicals and limit their damaging effects on our cells. Known antioxidants include vitamins such as vitamin C and E, minerals such as selenium and zinc, and certain enzymes in our body (MedlinePlus, 2017).

How does oxidative stress develop?

Oxidative stress can be triggered by various factors that either lead to overproduction of free radicals or a lack of antioxidants. Here are some of the most common causes:

• Environmental exposures: pollution, radiation, tobacco smoke
• Unhealthy diet: processed foods, sugar, unhealthy fats; lack of vitamins and minerals
• Excessive physical activity: intense exercise without sufficient recovery
• Chronic stress and sleep deprivation: prolonged psychological stress and poor sleep
• Diseases: chronic illnesses such as diabetes, cardiovascular disease, cancer
  

Source: Cleveland Clinic, 2022

Which diseases are caused by oxidative stress?

Oxidative stress plays a central role in the development and progression of many health conditions and diseases. Here are some diseases associated with oxidative stress:

• Cardiovascular diseases: Excess free radicals can damage blood vessel walls and promote inflammation, a process called lipid oxidation. This can lead to the formation of plaques in the arteries, a condition known as atherosclerosis. These plaques narrow the arteries and can eventually block them, increasing the risk of heart disease, heart attack, and stroke.
• Neurodegenerative diseases: Oxidative stress has been linked to the development of diseases such as Alzheimer’s, Parkinson’s, and multiple sclerosis. Free radicals and oxidative damage are believed to contribute to the degeneration of neurons in the brain.
• Diabetes: In diabetes, persistently high blood sugar levels lead to increased production of free radicals and reduced antioxidant defense, resulting in oxidative stress. This oxidative stress can worsen insulin resistance and thus aggravate diabetes.
• Cancer: Oxidative stress can damage DNA, leading to mutations. These mutations can contribute to the formation of cancer cells. Oxidative stress can also promote tumor growth (Reuter et al., 2010). 
• Aging: Oxidative stress is considered a key factor in the aging process. Continuous accumulation of oxidative damage over time can contribute to various signs and diseases of aging.
• Autoimmune diseases: In autoimmune diseases such as rheumatoid arthritis, ulcerative colitis, and lupus, oxidative stress is believed to trigger inflammatory responses that lead to tissue damage.
  

Sources: Cleveland Clinic, 2022; Liguori et al., 2018

These are just a few examples of the wide-ranging effects oxidative stress can have on health. It’s important to note that oxidative stress is only one of many factors that contribute to the development of these diseases. Genetic predispositions, environmental influences, and lifestyle choices also play a role.

How can oxidative stress be detected?

Measuring oxidative stress in the body can be complex, as there is no single universal test that can directly and definitively measure oxidative stress. Instead, various tests and biomarkers are used to assess the level of oxidative stress. Here are some of the most common methods:

• Measurement of antioxidants: Measuring the levels of antioxidants in the blood can provide insight into the level of oxidative stress the body is exposed to. A low antioxidant level may indicate increased oxidative stress.
• Measurement of oxidation products: When free radicals oxidize molecules like fats, proteins, or DNA, certain oxidation products are formed. These can be measured through blood or urine tests.
• Measurement of inflammation markers: Since oxidative stress is often associated with inflammation, certain inflammatory markers such as C-reactive protein (CRP) can also be used to assess oxidative stress.
  

Source: Katerji et al., 2019

It’s important to note that these tests should be performed and interpreted by medical professionals. Furthermore, detecting oxidative stress does not necessarily point to a specific disease, but rather to an imbalance in the body that can lead to health problems if not addressed.

What can I do about oxidative stress?

• Healthy diet: A balanced diet rich in antioxidants is an effective way to reduce oxidative stress. Antioxidants are found in many foods, including those containing vitamin C (such as oranges and strawberries), vitamin E (such as nuts and seeds), beta-carotene (such as carrots), selenium (such as fish and oysters), and zinc (such as meat and legumes).
• Sufficient exercise: Regular, moderate physical activity can help boost the production of antioxidants in your body and remove excess free radicals. For example, a 30-minute walk each day or a short yoga session can contribute to reducing oxidative stress.
• Stress reduction: Chronic stress can lead to increased production of cortisol, the stress hormone, which is associated with the production of free radicals. Stress-reducing techniques such as meditation, yoga, deep breathing, or other relaxation exercises can help lower stress levels.
• Adequate sleep: Sleep plays an important role in controlling oxidative stress. During sleep, your body produces melatonin, a hormone that also acts as an antioxidant. Therefore, getting enough high-quality sleep can help reduce oxidative stress (Teixeira et al., 2019). 
• Avoid harmful substances: Avoid substances that can contribute to oxidative stress, such as alcohol, tobacco, and other harmful drugs. Excessive sun exposure and air pollution can also increase the production of free radicals.
• Regular check-ups and testing: Regular medical check-ups and tests can help detect oxidative stress early and take appropriate action.

Source: Polijsak, 2011; Eske, 2019

Summary

Oxidative stress is a condition caused by an imbalance between the production of free radicals and the body’s ability to neutralize them. This state can lead to a wide range of diseases. However, there are several strategies to combat oxidative stress, including a healthy diet, regular physical activity, and adequate sleep.