What are antioxidants?

Veröffentlicht am: October 28, 2024
Irina  Fink
Irina Fink

Naturopath

Antioxidants perform many important functions in our body and are primarily used for cell protection, which benefits our overall health. Antioxidants occur naturally in many foods and help to scavenge and neutralize free radicals. 

Contents

What are antioxidants? 

Antioxidants are naturally occurring chemical substances that can specifically prevent the unwanted oxidation of other substances. It is therefore not a single substance, but rather a property or grouping of vital substances that play an important role in our diet and health.

Their main purpose is to keep our cells healthy by scavenging free radicals. In this way, they provide preventive protection against oxidative stress and resulting diseases such as cancer, dementia and rheumatism. It is therefore extremely important that we supply our bodies with sufficient antioxidants through our diet.

7 signs of oxidative stress and 7 ways to reduce it

The term "oxidative stress" is often used in the fields of science and nutrition. However, it is often not clear what it means for your health. The word oxidative suggests that oxidative stress has something to do with oxygen. Although oxygen is vital for us and we breathe it in all the time, it can cause great damage to the body. This is because oxygen forms aggressive compounds in the body that attack our cells. These compounds are called "free radicals". This is also known as an oxidation process, which destroys healthy cells and can have devastating consequences for our health. This causes cells to degenerate and subsequently leads to cancer and accelerates the ageing process.

Many research results indicate that oxidative stress is the fundamental cause of cancer. It is therefore advisable to inform yourself about this and avoid oxidative stress for your own well-being.

In this article, we will explain what is meant by the term and which symptoms indicate oxidative stress. You will also learn what you can do to prevent oxidative stress.

What is oxidative stress?

Oxidations always take place when our body processes the oxygen we breathe in and our cells generate energy from it. This also produces free radicals are released, which interact with the molecules in our cells and damage (or stress) nearby cells, MITOCHONDRIES and DNA (our genes).

Oxidation occurs due to a variety of circumstances, including

  • the processing of glucose in the cells for energy production
  • the fight against bacteria by our immune system and the triggering of inflammation
  • Detoxification processes in the body to break down harmful substances, pesticides and cigarette smoke

In fact, millions of processes take place in our body at any given time, during which oxidation occurs.

Physical and/or emotional stress leads to increased oxidation processes. As long as you have sufficient antioxidants, a careful balance is maintained and damage is avoided.

Oxidative stress occurs when the number of free radicals exceeds the number of antioxidants . Oxidation then damages our cells, proteins and DNA (genes).

HOW TO RECOGNIZE THAT YOU ARE SUFFERING FROM OXIDATIVE STRESS

Watch out for these symptoms:

  1. Tiredness
  2. Memory loss and/or brain disorders
  3. Muscle and/or joint pain
  4. Wrinkles and gray hair
  5. Reduced vision
  6. Headaches and sensitivity to noise
  7. Susceptibility to infections

Oxidative stress has also been linked to a number of health problems, including chronic fatigue syndrome, fibromyalgia, diabetes, Alzheimer's disease, anxiety, insomnia and cancer. It is very important to us to inform you about this and to enable you to prevent these problems.

HOW TO REDUCE OXIDATIVE STRESS

There are two ways in which you can reduce oxidative stress. Avoid exposing yourself to unnecessary oxidation processes and increase the number of antioxidants in your diet. Let's take a closer look at both options.

Reduce exposure to oxidation

As already mentioned, the more we are exposed to stress, toxins and infections, the greater the number of oxidation processes. They also increase with sugar consumption and chemicals. So the less you expose yourself to these things, the better.

Reach for organic foods and avoid toxins in your environment - both will make a big difference. It also helps if you reduce stress by taking the time to de-stress every day. The following four steps will help you reduce unnecessary oxidation in your body:

Step 1 - Avoid sugar and processed foods and keep your blood sugar levels in balance

Oxidation occurs in the body when sugar is processed. The more sugar we consume, the more oxidation takes place. Processed foods often contain sugar and/or other chemical additives that also oxidize. Large and irregular meals also trigger oxidative stress. Therefore, keep your blood sugar levels in balance and eat smaller meals regularly.

Step 2 - Prevent infections

Whenever your immune system fights an infection, oxidation takes place. Therefore, your body is deprived of energy as soon as you are ill. We recommend that you develop a strategy to avoid colds and infections. If you are regularly ill, develop a plan to avoid future infections.

Step 3 - Take time every day to reduce stress

It seems so simple and yet it pays off. It is extremely important that you plan enough breaks into your daily routine - this is the only way to give your body the chance to recover. Use the breaks you are entitled to (or create some) and see them as an opportunity to spend time in the fresh air, take a deep breath and regroup.

Here are a few suggestions for daily stress relief:

  • Sport
  • Meditation
  • Conversations with friends
  • Enjoy nature
  • Writing a diary
  • Entertaining television programs
  • Walk

Step 4 - Avoid toxins

Choose organic foods and avoid cigarettes, candles, hair and nail salons, carpets, exhaust fumes and plastic. Check your personal care and cleaning products for toxic ingredients and replace them with non-toxic ones.

Increase the number of antioxidants:

No matter what you try, you will not be able to avoid being exposed to a certain level of stress and toxins. Therefore, the next step is to increase the amount of antioxidants in your diet and consequently in your body. You can either help your body to produce them or take some in through food or supplements.

Antioxidants block oxidation. They crush them and render them harmless.

The last three steps for reducing oxidative stress follow. All steps increase the number of antioxidants in your body:

Step 5 - Promote the production of antioxidants

One of the most effective antioxidants is glutathione, which is formed in the body. It consists of the three amino acids glycine, glutamate and cysteine and contains sulphur. This is why it is so effective.

Eat foods that help your body to produce more glutathione:

  • Asparagus
  • Peaches
  • Walnuts
  • Spinach
  • Tomatoes

Consume foods with a high sulphur content so that your body produces more glutathione:

  • Garlic
  • Onions
  • Cruciferous vegetables such as broccoli, kale, collard greens and white cabbage
  • Avocados

Or you can take food supplements with the following nutrients:

  • N-acetyl cysteine (NAC)
  • Glycine
  • Glutamine
  • Methyl folate
  • B12
  • Selenium
  • SAM-e
  • Alpha lipoic acid

These supplements have also been shown to increase and maintain glutathione levels:

  • Vitamin C and E (prevent glutathione from oxidizing)
  • Zinc
  • Magnesium
  • Vitamin D
  • Milk thistle

It would be far too much to take all these products individually. We therefore advise you to take a combination product. Of course, you will need precise knowledge of your state of health. It is therefore best to choose the right product for you together with your doctor or a specialist.

Even high-quality multivitamin products contain antioxidants.

Preparations containing glutathione are also available on the market. These are particularly suitable for people with very low levels or for patients with a genetic SNP that depletes the supply. Please make sure that the product releases the nutrients gradually, is not soy-based and does not contain genetically engineered phosphatidylcholine to increase glutathione uptake.

Step 6 - Eat foods high in antioxidants

You can increase the number of antioxidants by including foods rich in antioxidants in your diet every day. In general, these are foods that are very colorful.

Examples:

  • Beet
  • Kale
  • Berries
  • Tomatoes

These foods also contain antioxidants:

  • Nuts and seeds
  • Green and black tea

And in spices like:

  • Cinnamon
  • Ginger
  • Curcumin (also known as turmeric)

The more antioxidants you consume, the better your body can react to oxidation processes and prevent oxidative stress.

Step 7 - Use herbs with a high antioxidant content

Studies suggest that there are four main plant sources of antioxidants:

  • Green tea
  • Curcumin (turmeric)
  • Quercetin
  • Resveratrol

There are also other useful sources of antioxidants in supplements that can be taken daily (either on their own or in combination with others).

Useful sources:

  • CoQ10
  • Selenium
  • Vitamin C

You have now learned a few ways to prevent oxidative stress and protect your cells. Provide your body with what it needs and avoid everything it doesn't need.

But what role do free radicals and antioxidants actually play in connection with oxidative stress and what exactly do they do in the body? We will now take a closer look at this and how you can incorporate sufficient antioxidants into your diet.

What are free radicals?

Atoms always form bonds. Either a chlorine atom (Cl) forms a bond with a hydrogen atom (H) or a carbon atom (C) forms a bond with 2 oxygen atoms (02). This results in the well-known carbon dioxide CO2, which is essential for all living organisms.

Atoms always have 8 molecules, the only exception is hydrogen, which has only 2 molecules. The term free radical means that 6 or 7 molecules are bound but 1-2 molecules remain unbound. These molecules are therefore highly reactive, unstable and short-lived.

They are keen to form bonds quickly. They can do this with valuable nutrients such as fats, proteins and carbohydrates. This reaction is unfavorable for the body, as these macronutrients are needed for energy production. 

 

Species

Name

Hydroxyl radical

HO°

Superoxiradical

O2°-

Alkoxyl radical

RO°

Peroxyl radical

ROO°

Singlet oxygen

1O2

Hydrogen peroxide

H2O2

Overview: Free radicals 

What are the causes for the formation of free radicals? 

Free radicals are produced in the body by overloading the combustion processes in mitochondria or by physical or chemical influences from outside. Free radicals can enter the body through the influences mentioned below by breaking down the body's molecules into free radicals from the outside. Free radicals can also enter the body by eating, drinking or inhaling anything that contains free radicals. For example, cigarette smoke and environmental toxins.

  • UV radiation
  • Smoking
  • Alcohol abuse
  • Ion radiation
  • Environmental toxins
  • Environmental pollution
  • Metabolic processes of metabolic oxygen
  • Inflammation
  • Hypertension (high blood pressure)
  • Diabetes mellitus
  • Overweight/obesity

A small amount of free radicals is not harmful, but an excess of free radicals can cause considerable cell damage.

Free radicals are everywhere in everyday life

We encounter free radicals in many places in our everyday lives: on the way to the office, to school or to the shops, we spend time in traffic and are exposed to harmful exhaust fumes. At work, we are surrounded by electrosmog and we add harmful substances to our bodies through food that has been heavily sprayed and treated with pesticides and fungicides. Alcohol consumption and smoking also contribute to cell damage.

Such cell damage occurs primarily when free radicals accompany us over a longer period of time and can accumulate in the body.

People are very often exposed to such situations, so it is important to beware of free radical attacks. On the one hand, the body protects its cells by removing free radicals via the urinary tract. On the other hand, the enzyme catalase protects the cells from free radicals by entering into this redox reaction. Hydrogen peroxide reacts to form oxygen and 2 molecules of water.

Damage from free radicals

This one unbound molecule can cause serious cell damage in the body. When free radicals attack healthy cells, this is oxidative stress. Free radicals damage numerous cell structures. They alter cell membranes, proteins and enzymes. Free radicals can also damage genetic material and are involved in the ageing process. They are also a frequent trigger or contributor to serious diseases.

Increased risk of diseases such as:

  • Arteriosclerosis
  • Rheumatism
  • Alzheimer's disease
  • Cancer
  • Sepsis (blood poisoning)
  • Increased oxidation of LDL (bad cholesterol)

There is also talk of visual impairment, strokes, high blood pressure and varicose veins in connection with free radicals.

The only "positive" property of free radicals

Free radicals are completely normal and, to a certain extent, necessary. They not only cause a certain amount of damage, but also promote repair. So the only positive property that free radicals have is that they protect the organism by participating in the killing process of microorganisms. Only when the amount of free radicals overwhelms the repair processes do they become a problem. This is what we call oxidative stress. Therefore, this is not an explainable reason why you should not protect yourself against free radicals. The negative properties of free radicals predominate and it is therefore very important to prevent free radicals and provide yourself with sufficient antioxidants.

Antioxidants for defense

You can protect yourself from damage caused by free radicals by avoiding or limiting the causes mentioned above. You can also protect yourself against free radicals with the right diet by consuming antioxidants. If there are enough antioxidants in the body, our cells are protected from the attacks of free radicals.

The reason for this is that harmful free radicals are missing an electron. The free radicals can be seen as predators, so to speak, because they steal the missing electron from healthy cells and damage them. Antioxidants, on the other hand, voluntarily give up an electron and thus prevent the free radicals from attacking the cells. You could therefore say that antioxidants are the health police that catch the free radicals.

Function of antioxidants and impact on our health

Antioxidant substances eliminate free radicals by binding them permanently. In this way, they are gradually removed from the body. This improves the damaged tissue and no further tissue is destroyed. This improves skin regeneration.

According to studies, these radical scavengers are said to have a positive effect on skin ageing. Skin ageing is reduced and the skin provides more moisture, resulting in an anti-ageing effect.

Restoring and protecting the tissue also reduces the risk of diseases such as rheumatism, arteriosclerosis, Alzheimer's and cancer.

Antioxidants against diseases

Preventing Alzheimer's with antioxidants

Diseases such as Alzheimer's or Parkinson's are triggered by oxidative destruction of nerve cell tissue. This is caused by free radicals. Antioxidants such as vitamins C and E are able to prevent this process, i.e. oxidative stress. If you make sure you have a sufficient intake of antioxidants, you reduce the risk of developing Alzheimer's disease.

Antioxidants against cancer

If our body is exposed to free radicals over a longer period of time, this increases the risk of developing cancer. This is because free radicals are able to change the genetic material in the cells, i.e. the DNA. This change can cause the cell to divide uncontrollably, multiply and develop cancer. However, damage to healthy cells can be prevented with antioxidants.

Carotenoids are powerful antioxidants and act as cancer protection

Carotenoids also belong to the group of secondary plant substances and are natural colorants found in many types of fruit and vegetables. They are found in yellow, red and orange fruits such as carrots, peppers, tomatoes, apricots and oranges. However, green vegetables such as broccoli, spinach and peas also contain carotenoids. However, they are not visible here because the chlorophyll, the green pigment, masks them.

Carotenoids have a high antioxidant power and have an anti-inflammatory effect.

Carotenoids are particularly active in the skin to prevent cancer. They are like a natural sunscreen from the inside, as they are deposited in the skin as pigments that reflect sunlight. This can reduce cell damage caused by UV radiation.

Due to the many health-promoting properties of carotenoids, it is particularly important to ensure a sufficient intake. To enable the body to absorb and utilize the carotenoids better, we recommend that you prepare foods containing carotenoids with added fat or oil or in cooked form.

Antioxidants offer protection for the heart and circulation

Smoking, being overweight, a lack of exercise or an unbalanced diet can be a real burden on our heart. They are often the cause of cardiovascular diseases such as arteriosclerosis and the associated development of strokes and heart attacks. However, antioxidants can prevent this. Vitamin C, for example, helps to keep our blood vessels elastic and has a positive effect on blood pressure. Vitamin E prevents cholesterol from settling on the blood vessel walls and can therefore prevent blood clots. 

Which antioxidants work particularly well?

Vitamins such as vitamin C, vitamin E and beta-carotene, which is the precursor of vitamin A, have the greatest effect. Selenium, sulphur and zinc are also of great benefit in this task.

However, antioxidants not only fulfill a function as radical scavengers but are also responsible for other processes in the body. Vitamin C is responsible for the formation of collagen in the connective tissue, which ensures a firm and healthy complexion. Carotenoids protect us from the sun by being responsible for pigment formation in the skin. Vitamin E plays a role in cell renewal and helps the skin to heal more quickly in the event of injuries. It is also responsible for a healthy and strong hair structure. While selenium is responsible for the function of the thyroid gland, sulphur has a detoxifying effect and zinc has a positive effect on the eyesight.

They also have antioxidant properties:

  • OPC
  • Astaxanthin
  • R-alpha lipoic acid
  • Omega-3 fatty acids
  • Coenzyme Q10
  • Green-lipped mussel extract
  • L-carnosine

Studies on the topic of antioxidants 

Intervention studies of various antioxidants:

Studies have shown that a daily intake of up to 10 mg/d of β-carotene via food is considered safe.

The antioxidant beta-carotene is found in carrots, sweet potatoes, pumpkin, tomatoes, asparagus, peas and much more. 

For α-tocopherol, also known as vitamin E, no preventive effect with regard to overall mortality, the risk of cardiovascular (blood supply to the heart) mortality or cerebrovascular (blood supply to the brain) events could be shown in the intervention studies. 

The super antioxidant vitamin C leads to a 50 % reduction in flu-like infections in top athletes.

There is no preventive effect in the normal population, but the duration of illness can be reduced by 8% in adults and 13% in children.

Which foods contain which antioxidants?

Here is an overview:

  • Vitamin C: citrus fruits, kiwi, strawberries, currants, rose hips, sea buckthorn, spinach, papaya, fennel, kale and peppers
  • Vitamin E: Nuts, eggs, cereal products and cold-pressed safflower, grape seed, sunflower or wheat germ oil
  • Carotene and other carotenoids: carrots, tomatoes, apricots and dried fruit
  • Selenium: Garlic, whole grains, brewer's yeast, eggs, liver             
  • Sulphur: pulses and protein-rich animal foods
  • Zinc: wheat germ, wholegrain products, liver, seafood and nuts

Absorption of antioxidants

For our health, we should pay attention to a balanced and varied diet, as this is the most important thing for a sufficient intake of antioxidants. Valuable antioxidants are mainly found in fruit that has been allowed to ripen for a long time. Regionality is therefore the top priority if you want to get the most out of these free radical scavengers. Regionality also has the advantage that the fruit has a short transportation route and is therefore exposed to fewer harmful substances. Seasonality also plays an important role. If we buy tomatoes or peppers from pickled greenhouses in winter, for example, this increases pollutant emissions and puts a strain on the environment.

According to this, fruit and vegetables from the region that are grown and harvested at the right time of year contain the most antioxidants. These are found as vitamins, minerals, trace elements, enzymes and secondary plant substances. Antioxidants are also found in herbs, spices, sprouts, cold-pressed vegetable oils, nuts and even cocoa.

The so-called ORAC value is particularly high in these foods. ORAC stands for Oxygen Radical Absorbance Capacity. This value indicates how much antioxidant power is contained in a food.

People who are frequently exposed to free radicals in everyday life should take additional protection with antioxidants, possibly in the form of food supplements. For example, vitamin C, vitamin E, OPC, omega-3 and glutathione.

What is the best way to preserve the valuable antioxidants?

According to experts, we can meet our need for these antioxidants by including 200 grams of fruit and 450 grams of vegetables in our diet every day.

It is not only important to buy regional and seasonal produce. We also need to pay attention to the right type of preparation if we want to increase the number of valuable antioxidants in our meals. Many vitamins are sensitive to heat, for example vitamin C, vitamin B1, B6, B12 and folic acid. Some minerals or trace elements, such as magnesium, potassium and zinc, on the other hand, are water-soluble. Incorrect preparation, such as cooking for too long or adding too much water, can result in the loss of important antioxidants.

Here are a few helpful tips to avoid this:

  • Prefer cooking methods such as steaming or stewing. When cooking, many vitamins, minerals and trace elements dissolve in the water and are not retained in the food.
  • If you are cooking, do not throw the water away. You can add the remaining water with the nutrients dissolved in it to soups or sauces.
  • If possible, vegetables should be cooked with the skin on and preferably as a whole piece. This means that the nutrients from the peel do not end up in the organic waste, but are absorbed into the food during cooking.
  • If you prepare a freshly squeezed juice or smoothie, enjoy it straight away. If it sits around for too long, many antioxidants are lost.
  • It is the same with other foods. Do not store food for a long time, but use it as fresh as possible.

Powerful antioxidants and superfoods

OPC from grape seeds as a power antioxidant

OPC is a polyphenol and belongs to the group of secondary plant substances. OPC (oligomeric proanthocyanidins) is extracted from grape seeds. It is said to have a particularly high antioxidant power. This is mainly because it enhances the effect of other antioxidants such as vitamin C and vitamin E. As these are excellent radical scavengers, it is possible to prevent cancer.

In addition to cell protection, OPC has many other benefits in the body. Among other things, it stabilizes the structure of collagen in our skin, which reduces wrinkles, makes our skin look firmer and younger and promotes wound healing. In the hair, OPC acts on the collagen structure and makes it look fuller and healthier.

It is also extremely important for the health of the blood vessels, as it helps to maintain the elasticity of the blood vessel walls. This in turn has an extremely positive effect on blood pressure and subsequently on our heart health.

Another benefit of OPC is its effect on our eyesight, as it can prevent cataracts and help us to see better in the dark.

OPC is also said to help allergy sufferers. This is because it acts as an anti-histamine and therefore naturally alleviates allergy symptoms such as sneezing, watery eyes or itching.

Phenolic acid - the antioxidant power of the pomegranate

The pomegranate - or the food of the gods - has a particularly health-promoting effect. It is not for nothing that it has been used in traditional medicine for thousands of years. Pomegranates have a particularly high content of flavinoids and polyphenols, which play an important role in cell regulation. Pomegranates are rich in vitamin C, calcium and iron. It is therefore effective against oxidative stress.

Ellagic acid is a particularly effective polyphenol found in this power fruit. As it has a high antioxidant power, it helps to neutralize harmful free radicals in the body. Furthermore, the high content of polyphenols helps to alleviate chronic inflammatory skin diseases.

The fruit is also very important for our cardiovascular health, as the secondary plant substances in pomegranates ensure that our heart and blood vessels remain elastic. This can significantly improve blood circulation and lower high cholesterol levels.

Coffee - not just a pick-me-up but also contains healthy antioxidants

Coffee contains several antioxidants, including flavonoids, chlorogenic acids, resveratrol and melanoidins. These are said to prevent cardiovascular disease, cancer, depression and Alzheimer's disease. However, the antioxidant power varies depending on the degree of roasting. Light and medium roasts are more effective than dark roasts. If the coffee beans are roasted too much, valuable antioxidants are lost.

As coffee is very sensitive to light, special care must be taken when storing it. We recommend storing coffee in a container that is protected from light and air. Coffee provides the most antioxidants when it is drunk black. Adding milk reduces the power of the antioxidants. This is because the milk protein casein binds to the antioxidants and thus reduces their effect.

Matcha tea - the green miracle antioxidant

Unlike conventional green tea, matcha tea is not made from the leaves but from the buds of the tea plant, which are then processed into powder. The concentration of nutrients in this powder is much higher than in ordinary teas, as it contains up to 137 times more antioxidants. These include catechins, which belong to the group of polyphenols. This antioxidant ensures that the metabolism is accelerated, burns fat and lowers the LDL cholesterol content in the blood. It can therefore prevent heart disease.
It is also active as a free radical scavenger and protects cells from liver and kidney damage in particular. Matcha tea owes its bright green color to the dye chlorophyll, which has a detoxifying effect on the body.

Good to know: Matcha tea is of high quality if the color is bright green and does not taste too bitter but rather sweet.

Garlic - the antioxidant power of the bulb

Even if the intense smell of garlic may seem unpleasant, especially after eating it, it has a great benefit for our health. This smell comes from the sulphur compound allicin, which develops its antioxidant effect in our body. Garlic contains the precursor of allicin, alliin. As soon as the garlic is peeled or chopped, the enzyme allinase comes into play and reacts with the alliin. This results in the formation of the antioxidant allicin.

The ingredients in garlic not only act as free radical scavengers but also as a natural antibiotic, which can counteract inflammation and contribute to the health of the intestinal flora.

Goji berries - small in size but big in effect

Goji berries are considered a superfood because they contain a variety of nutrients and antioxidants that are enormously beneficial to our health. Traditional Chinese medicine has long been aware of the power of goji berries. They have been used there for over 5000 years as a remedy and to prevent illness.

Goji berries have a high content of carotenoids, especially beta-carotene. This can help to protect our skin and the retina in our eyes from sun damage.

In addition to carotenoids, the small miracle fruits also contain vitamins A, B, C and E, minerals such as iron, magnesium, phosphorus and potassium. Goji berries can also help with colds, as trace elements such as copper, manganese, chromium, selenium and zinc help our immune system to defend itself.

Curcuma - turmeric as a natural remedy and antioxidant

The yellow-orange spice from South Asia is a true medicinal plant and belongs to the ginger family. The main active ingredient in turmeric root is curcumin, which belongs to the group of secondary plant substances and can have extremely positive effects on the body. Curcuma is said to have antioxidant and anti-inflammatory properties. For example, curcumin can relieve swelling and associated pain in arthritis. Furthermore, curcuma lowers the LDL cholesterol content in the blood, which makes a positive contribution to the health of the heart and blood vessels and thus prevents heart attacks and strokes.

As you can see, valuable antioxidants really are found in many foods. We just need to incorporate them sufficiently into our diet. And if we follow a few helpful tips, it is even easier to provide our body with enough antioxidants. In this way, we can protect our body and remain vital and efficient.

 

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