Antioxidants: What They Are, Their Role in Health, and Where to Get Them

Antioxidants play an important role in maintaining health, as they help protect the body's cells from damage caused by free radicals. These radicals, which are byproducts of metabolism and environmental influences, can cause oxidative stress, which, in turn, is associated with the development of various diseases, such as cancer, heart disease, and premature aging.
Eating foods rich in antioxidants helps neutralize these harmful compounds, thereby reducing the risk of many chronic diseases. Such foods include fruits, vegetables, nuts, and whole grains, which provide the body with the substances necessary to maintain its functioning and prevent the negative effects of oxidative stress.
Thus, antioxidants not only contribute to overall health but also help maintain long-term well-being.
Oxidative stress is a condition in which there is an imbalance between the formation of free radicals and the body's ability to neutralize their effects with antioxidants. Free radicals are unstable molecules that can damage cellular structures such as DNA, proteins, and lipids. When the number of these molecules exceeds protective levels, this can lead to cellular damage and various diseases, including cardiovascular disorders, cancer, and neurodegenerative diseases. Thus, oxidative stress plays a significant role in aging and the development of many pathologies, emphasizing the need to maintain a balance between oxidative processes and antioxidant defenses in the body.
Antioxidants are substances that help protect the body from damage caused by free radicals. Free radicals are unstable molecules that form during metabolism and as a result of external factors such as pollution, ultraviolet radiation, or smoking. They can cause oxidative stress, which can lead to cell damage and the development of various diseases.
Antioxidants neutralize free radicals by donating electrons to them, thereby preventing their destructive effects. These substances can be of both synthetic and natural origin. Well-known natural antioxidants include vitamins C and E, beta-carotene, and flavonoids found in plants.
When ingested, antioxidants can help slow the aging process, reduce the risk of chronic diseases such as cardiovascular disease and cancer, and maintain overall health. A balanced diet rich in antioxidants helps strengthen the immune system and improve overall well-being.
Food provides a variety of antioxidants, which play an important role in protecting the body from free radicals. Some of the most well-known antioxidants include vitamins C and E, which can be found in citrus fruits, berries, nuts, and vegetable oils. Additionally, beta-carotene, found in carrots, sweet potatoes, and green leafy vegetables, also has antioxidant properties. Flavonoids, found in tea, apples, red wine, and chocolate, are another group of powerful antioxidants. Selenium, found in Brazil nuts and seafood, is also an important element that helps reduce oxidative stress. Thus, a varied and balanced diet that includes these foods can significantly increase antioxidant levels in the body and support its health. The reasons why "live" antioxidants may be preferable to dietary supplements are varied and multifaceted. Firstly, natural antioxidants found in fresh fruits and vegetables have complex structures and compositions, which ensures their more complete absorption by the body. They work synergistically, enhancing each other's absorption and effectiveness, which cannot be replicated in synthetic supplements.
Furthermore, plant-based foods contain not only antioxidants but also many other bioactive components, such as vitamins, minerals, and fiber, which enhance their beneficial properties. These compounds help the body fight oxidative stress more effectively than isolated substances.
Another important aspect is that "live" antioxidants are generally less susceptible to changes during storage and preparation, which helps preserve their beneficial properties. Unlike supplements, which can lose their potency, natural sources of antioxidants remain stable and potent when stored and prepared properly.
In summary, it can be argued that natural antioxidants from fresh foods represent a more balanced and effective way to protect the body from free radicals compared to synthetic dietary supplements.
There are several ways that can help increase antioxidant production in the body. First of all, it's important to pay attention to your diet. Including foods rich in vitamins C and E, as well as selenium, can significantly boost levels of these protective substances. Fruits and vegetables, especially brightly colored ones like berries, spinach, and carrots, contain many antioxidants that are beneficial for health.
It's also important to monitor your physical activity level. Regular exercise improves metabolism and activates processes associated with antioxidant production. It's also helpful to avoid unhealthy habits such as smoking and excessive alcohol consumption, as they can significantly reduce levels of these protective compounds in the body.
Don't forget the importance of adequate sleep and stress management. Chronic stress can negatively impact health and reduce the effectiveness of antioxidant protection. Relaxation-focused practices such as meditation or yoga can be very helpful.
You should also consider adding natural supplements containing plant extracts, such as curcumin or resveratrol, which are known for their antioxidant properties. It's important to remember that optimal antioxidant production requires a comprehensive approach that includes a healthy diet, physical activity, and self-care.

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The Role of Antioxidants in Maintaining Health

Antioxidants are substances that help regulate the levels of free radicals in our body. To better understand the role of antioxidants, it is useful to first understand how free radicals are formed and how they can threaten our health.

The body undergoes many daily processes in which oxygen is actively involved. Some of this gas is used in the respiratory chain to produce energy, while another part is spent on the synthesis of reactive oxygen species, such as superoxide anion, hydrogen peroxide, and hydroxyl radical. These compounds make up free radicals.

In a healthy body, oxygen free radicals play an important role in two key processes: they promote the destruction of old cells and accelerate the formation of new ones [2]. All cells in the body are capable of generating oxygen free radicals to meet their needs. These molecules also become our allies in the fight against infections: they damage bacterial membranes and support immune cells in their defense against infections, and then cleanse the body by replacing damaged molecules with new ones [3]. However, there is one significant problem: free radicals are unstable molecules. When their numbers exceed the normal range, they begin to oxidize various substances, leading to cellular damage. The instability of these compounds is due to the presence of an unpaired electron in the outer orbit. It is this electron that makes the radicals prone to rapid chemical reactions. As a result, one free radical can oxidize fatty acids, resulting in the formation of new radicals. This process unfolds in a chain reaction, and it can only be stopped with the help of antioxidants.

A lack of antioxidants can lead to free radicals causing significant damage to the body, which can ultimately be fatal.

Understanding Oxidative Stress: Definition and Meaning

When the number of free radicals exceeds the level of antioxidants, it can lead to a condition known as oxidative stress. This term is associated with stress because the functioning of cellular processes is under intense pressure, which can lead to DNA damage and slower regeneration. As a result, cells begin to age faster and die. To date, more than 200 different diseases have been linked to oxidative stress. However, this condition does not occur instantly; It develops under the influence of many factors over a long period of time.

There are many reactive oxygen species that are formed as a result of:

exposure to ultraviolet radiation (for this reason, you should use a cream with SPF in the sun);
psychological stress;
smoking;
regular consumption of alcoholic beverages;
taking medications;
physical activity;
inflammatory processes;
any infections;
excess weight [3].

Under normal circumstances, oxidative stress does not occur, since antioxidants effectively eliminate the negative effects of oxidants. However, it is worth noting that the antioxidant system is not unlimited, and with an excess of free radicals, its reserves may be insufficient.

Mechanisms
Without developed protective mechanisms, such as the antioxidant system, living beings would not be able to adapt to the conditions of an oxygen-saturated atmosphere, as well as to the effects of ultraviolet radiation and natural radiation. These protective systems arose in the process of long evolution, allowing the organism to survive in unfavorable conditions.
Antioxidants are able to block the action of free radicals by transferring electrons to them. During this reaction, an antioxidant donates its electron to a radical, which leads to the neutralization of the active form of the radical and the formation of a neutral molecule. Thanks to this mechanism, the chain reaction is interrupted, preventing the further formation of new free radicals.

Sources of oxidants in our diet

The body has an antioxidant system designed to quickly replenish its reserves. When an antioxidant is used, it is restored and ready for new action! Two types of antioxidants are involved in this process: direct antioxidants, which directly neutralize free radicals, and indirect antioxidants, which promote the formation of new molecules. To ensure the effective functioning of this system, it is important to choose foods that contain the following antioxidants.

Vitamin E is a complex of eight different compounds. The most active of these is alpha-tocopherol, which can stop oxidative chain reactions and prevent the formation of new free radicals. For the antioxidant system to function properly, adults need 15 mg of tocopherol daily, while children require 3 to 15 mg depending on age.

Vitamin C is a water-soluble vitamin with direct antioxidant properties. In addition, it is able to restore other antioxidants, such as vitamin E.

According to research, vitamin C is able to accumulate inside immune cells, providing them with protection when interacting with oxidizing molecules.

However, the human body is not able to store vitamin C for a long time, so adults need to get it from food in an amount of 100 mg daily, and children - from 30 to 90 mg every day.

Beta-carotene is a compound that is transformed into vitamin A in the body. Researchers have identified over 600 different chemicals belonging to the group of carotenoids, which have antioxidant properties. Beta-carotene is especially present in orange, red, and green foods. On average, a person needs to get from 2 to 7 mg of beta-carotene daily.

Lycopene is a fat-soluble antioxidant that can be found in red and pink foods. Interestingly, the brighter the color, the more lycopene is contained in a given product. Its ability to eliminate free radicals is twice that of beta-carotene and ten times that of vitamin E. The body requires only a small dose of lycopene—about 5 milligrams per day.

Selenium is a mineral with antioxidant properties that is present in the soil and absorbed by plants during their growth. Brazil nuts are the richest source of this element, but selenium can also be found in foods such as mushrooms, brown rice, and oats. This mineral plays a key role in the synthesis of an enzyme called glutathione peroxidase, which is responsible for the breakdown of hydrogen peroxide in cells, thereby protecting them from potential damage. To maintain optimal glutathione levels, a person needs to consume 20 to 100 mcg of selenium daily.

Interest in flavonoids began to develop in the 1990s, when the so-called "French paradox" was discovered. The French lifestyle isn't exactly exemplary in terms of health: their diet is high in fat, their physical activity leaves much to be desired, and smoking is common. However, they have a much lower incidence of cardiovascular disease, and on average, they live longer than people in other countries. This "paradox" was explained by the French's significant consumption of flavonoids, primarily from red wine. Flavonoids are a large group of compounds that give fruits and vegetables their characteristic colors—such as orange, bright red, deep blue, green, or yellow.

The optimal daily intake of flavonoids for adults is 250 mg, while for children the recommended dose is in the range of 150 to 250 mg.

Omega-3 fatty acids, which are represented by three varieties, are vital for the normal functioning of the body. Alpha-linolenic acid (ALA) is one of them and is considered essential. The body can produce the other two acids on its own, albeit in limited quantities, from ALA.

The daily requirement for ALA is directly related to a person's age and gender. Adult men require 1.6 mg of ALA per day, while women need 1.1 mg. Children need this substance in an amount of 0.5 to 1.6 mg per day.

Astaxanthin is a carotenoid and a fat-soluble pigment. This antioxidant molecule has a unique structural organization, allowing it to be found both inside and outside cell membranes. This feature allows astaxanthin to provide more effective protection against free radicals than beta-carotene and vitamin C. The main sources of astaxanthin are seafood.

The European Food Safety Authority (EFSA) recommends limiting daily astaxanthin intake to 8 mg.

Coenzyme Q10, also known as ubiquinone, is a compound with properties similar to vitamins [30]. One of its unique properties is its ability to be restored by the human body's enzymatic systems, while other antioxidants lose their activity after neutralizing free radicals. The recommended daily intake of coenzyme Q10 for adults is 30 mg [12].

Benefits of "live" antioxidants versus supplements

Antioxidants are also available in supplement form, which are often marketed as "ultra" or "high dose." While such advertising may be appealing, it is important to remember that too many antioxidants are not always beneficial. In high doses, they can be toxic and, in some situations, even promote oxidative stress rather than prevent it.

The benefits of antioxidants are not always determined by their presence in pure form, but depend on how they interact with other substances present in whole foods. A study conducted by scientists from the University of Milan revealed interesting results [33]. Participants in the study were divided into two groups: one was given 300 ml of natural orange juice for two weeks, while the other group was given the same amount of a drink with added sugar and vitamin C. Although the vitamin content in both drinks was identical, by the end of the study, it was clear that natural orange juice demonstrated a significantly more pronounced antioxidant effect.

The optimal option for safely and beneficially obtaining antioxidants is to consume foods containing them in significant quantities. By eating a varied diet, we provide our bodies not just with individual antioxidants, but with a complete set of these substances.

However, it should be emphasized that the origin of a specific product must be investigated. If fruits or vegetables were grown in unfavorable conditions, for example, on poor soil, then they are unlikely to have accumulated a significant amount of nutrients.

Ways to stimulate antioxidant production in the body

Quitting smoking. Tobacco smoke contains a large number of toxic substances, including those that can increase oxidative stress in the body. Therefore, smokers need to consume more antioxidants to offset the negative effects of cigarettes. For example, smokers' daily requirement for vitamin C increases by 35 mg.
You shouldn't give up meat products. Meat contains a sufficient amount of cysteine, which is a powerful antioxidant because it acts as a precursor to glutathione.
Reduce your consumption of unhealthy foods. If dishes can be characterized as "sweet," "fatty," or "fried," then after eating them, the body will require a significant amount of antioxidants for recovery.
Get a good night's sleep. During a night's rest, our body produces the neurohormone melatonin, which is commonly called the sleep hormone. However, its functions are not limited to this—it also has significant antioxidant properties. Melatonin can effectively neutralize free radicals and support the functioning of the glutathione peroxidase system. In order for melatonin to be produced, two conditions must be met: complete darkness and the presence of the amino acid tryptophan.

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