What is oxidative stress? - simply explained

Oxidative stress and free radicals are increasingly linked to an unhealthy lifestyle. However, knowledge on the subject is often shaped by dangerous half-truths. This article will explain oxidative stress in simple terms. Who is affected by it? What are the potential causes? And how can oxidative stress be reduced?

Under normal physiological conditions, the human body does not experience oxidative stress. The oxidative and antioxidative processes in human cells are balanced. However, under certain circumstances, this balance in the body can be disrupted, leading to an above-average concentration of oxidatively active molecules. Oxidative molecules include reactive oxygen species (ROS), reactive nitrogen species, and free radicals.

The imbalance between oxidants and antioxidants is known as oxidative stress. Oxidative stress can result from both an increased formation of free radicals and a loss of activity or concentration of antioxidants.

To avoid the increased production of free radicals and oxidative molecules in body cells, a healthy lifestyle should be maintained. According to a study by the Robert Koch Institute (2008), the following tips should be observed:

More fruits and vegetables (approximately 5 portions of fruits and vegetables, totaling at least 650g, should be consumed).

➤ Fruits and vegetables provide plant-based antioxidants, have a low energy density, and thus a low oxidative load, which will reduce oxidative stress in the long term.

Less meat (In particular, the consumption of red meat should be reduced. A maximum of 600g of meat per week should be consumed).

➤ Meat products, and especially red meat, have a high iron content. Excessive iron intake has a pro-oxidative effect. Furthermore, animal fats cause oxidative stress through postprandial hypertriglyceridemia.

Less fat (A maximum of 80g of fat per day should be consumed).

➤ Fat intake should be reduced, as it also has a pro-oxidative effect through postprandial hypertriglyceridemia.

Less sugar (Foods or drinks containing various types of sugar, such as glucose syrup, should be consumed or drunk as rarely as possible).

➤ The high glycemic index of sugar has a pro-oxidative effect.

➤ Do not smoke, tobacco smoke contains various substances that have an oxidative effect. A single puff of a cigarette can lead to immense formation of free radicals.

Physical activity (At least 30 minutes of moderate physical activity is recommended).

➤ Physical activity reduces the formation of free radicals in the mitochondria.

Oxidative stress is associated with the development of chronic diseases such as cancer, eye diseases, diabetes, arthritis, or cardiovascular diseases. In addition to accelerated aging and the formation of wrinkles, oxidative stress also leads to a loss of certain functions of proteins, lipids, and DNA, which can be counteracted with the help of CBD oil.¹

Furthermore, one should reduce the risk of exogenous factors contributing to increased free radical formation by avoiding environmental toxins (wearing respiratory protection if necessary).

A balanced diet, in particular, plays a crucial role in the fight against oxidative stress. In addition to sufficient consumption of fruits and vegetables, antioxidants can be well absorbed through dietary supplements.

Free radicals are highly reactive atoms, molecules, or ions. Free radicals are an intermediate product of metabolism and are formed when a hydrogen atom combines with an oxygen atom in the respiratory chain of cells and further reacts to form reactive oxygen compounds. The formation of free radicals can lead to chain reactions, ultimately resulting in an imbalance between free radicals and antioxidants, which eventually causes oxidative stress.

When in balance, free radicals have a variety of positive properties for the body. For example, they contribute to:

• Strengthening the immune system (white blood cells and macrophages use free radicals to destroy bacteria)
  
  
• Activation of mitochondria
  
  
• Apoptosis (programmed cell death, which plays a crucial role in cancer suppression)

Free radicals and the body's defense mechanisms work together. Thus, free radicals promote health and ward off disease. However, the balance between free radicals and antioxidant molecules must always be maintained to promote a healthy lifestyle. The question now is what properties antioxidants have.

Antioxidants are substances like proteins, peptides, and low molecular weight compounds that combat free radicals. These substances help to slow down or even prevent the oxidation of oxidative molecules (especially free radicals). There are endogenous antioxidants (influenced by endogenous factors), for example, the human enzyme system.

However, there are also exogenous antioxidants (influenced by exogenous factors), such as micronutrients and phytochemicals, which can help the body to scavenge free radicals and thus contribute to a healthier lifestyle. Endogenous antioxidant molecules are considered to have higher relevance in science. However, their function is also linked to the sufficient presence of micronutrients such as iron, manganese, and zinc.

Important antioxidants include:

• Micronutrients (Vitamin A, Vitamin C, Vitamin E, alpha-lipoic acid)
  
  
• Trace elements such as iron and zinc
  
  
• Secondary plant compounds such as flavonoids or phytocannabinoids (CBD, CBG, CBDa)

Antioxidant molecules are therefore naturally formed on the one hand, and on the other hand, the development of these molecules can be promoted through diet and dietary supplements. A varied diet with plenty of fresh and unprocessed fruits and vegetables increases the intake of exogenous antioxidants and promotes the formation of endogenous antioxidants. A healthy diet therefore plays a crucial role in reducing or preventing oxidative stress.

Oxidative stress arises when free radicals are not adequately countered by antagonists (antioxidants). But how does this excess of oxidative molecules come about?

Various factors can contribute to an excess of free radicals over antioxidants. An unbalanced diet, an unhealthy lifestyle (smoking, alcohol, drugs, little exercise), and environmental conditions are crucial factors that contribute to both increased production of free radicals and reduced production of antioxidants. The influences can be divided into endogenous and exogenous factors.

Endogenous factors that lead to oxidative stress are not directly influenced by lifestyle or the environment. These include:

• A weak immune system
• Inflammation
• Injuries
• Operations
• Allergies

Even if endogenous factors contributing to oxidative stress are not directly controllable, they can be reduced with the help of a balanced lifestyle. Plenty of fruits and vegetables, for example, can strengthen the immune system.

Exogenous factors that lead to oxidative stress are directly influenced by lifestyle or the environment. Behaviors and external influences that have a direct impact on free radicals include, for example:

• Consumption of tobacco, alcohol, and drugs (a single puff of a cigarette can already generate 10¹⁵ free radicals. This corresponds to about 100 times the number of human body cells)
  
  
• Air pollution (ozone, particulate matter, nitrogen oxides)
  
  
• A one-sided and inadequate diet
  
  
• Increased physical exertion (high-performance sports, strenuous & physical labor)
  
  
• UV radiation
  
  
• Environmental toxins (heavy metals, asbestos, etc.)

Oxidative stress can become noticeable when it becomes a chronic condition. The excess of free radicals and other oxidants attacks cells. This can lead to diseases, organ damage, and an accelerated aging process. Oxidative stress causes long-term skin aging and the appearance of wrinkles.

In a scientific article from 2019, a scientist from Pennsylvania State University found that various studies demonstrate a connection between shortened telomeres and oxidative stress. Telomeres are parts of DNA. During cell division (i.e., aging cells), they shorten with each cell division. Researchers see a direct correlation between telomere length and the biological age of cells.

It is believed that oxidative stress is partly responsible for:

• Chronic diseases
• Cancer
• Cardiovascular diseases
• Alzheimer's, strokes, and Parkinson's

Various tests exist that can determine, through urine and plasma analysis, whether an imbalance between oxidants and antioxidants is present. These tests aim to ascertain the extent to which the organism can defend itself against free radicals.

Even if one is unsure whether an oxidative stress condition exists or not, certain recommendations should be observed to ensure sufficient antioxidants. In addition to adequate antioxidants, a healthy lifestyle also leads to a strong immune system and an adequate supply of vital substances.