Antioxidant: Our defense against aggressive free radicals

Antioxidant: Unsere Abwehr gegen angriffslustige freie Radikale

"With antioxidants, the skin stays younger for longer" - you will have heard this statement at the latest when you find out about anti-aging skin care products. But what does that mean and is it actually true or is it just one of many commercial slogans? Many don't really know what to do with antioxidants, which is why we investigated the topic.

In our article on the topic of antioxidants, we try to explain everything about the tasks and occurrences of this chemical compound. Among other things, we go directly into the antioxidant itself and give you the foods that are best suited as an antioxidant supplier.

the essentials in brief

  • Antioxidants are said to protect humans from diseases. This is done by neutralizing so-called "free radicals"
  • Some of the many effects of antioxidants are: Protection against early cell aging, against disease and against general cell deterioration
  • Normally, antioxidants are sufficiently absorbed through a healthy and balanced diet, but if this is not the case, special dietary supplements can be used

Background: What are antioxidants?

In our guide we answer the most important questions about antioxidants and their effects.

What is meant by antioxidant?

An antioxidant is a chemical compound (small molecular group or enzyme) that prevents the oxidation of harmful substances in the body and thus protects our organism.

What is the role of antioxidants in our body?

Antioxidants neutralize so-called free radicals and thus prevent oxidation. For this reason, these are often referred to as "radical scavengers". They react with the incomplete oxygen compounds and prevent or slow down cell oxidation. Accordingly, diseases and inflammation are prevented.

What are free radicals?

Free radicals are incomplete and unstable compounds. They only have one unpaired electron, so they are missing another electron. Because of this, they want to react immediately with another substance in order to achieve a stable and complete state. During this process, an electron is snatched from the other substance. The reaction triggers an ongoing process and more free radicals are formed.

Such free radicals are formed during various metabolic processes. But external influences such as alcohol, drugs, UV rays or the inhalation of environmental toxins also cause the formation of free radicals.

Why are free radicals dangerous?

Because free radicals steal an electron from other chemical compounds, the other cell can be severely damaged and its cell function impaired. In the worst case, the DNA is damaged so that the damage is passed on during cell division.

We speak of "oxidative stress" when the proportion of oxygen radicals is too high. If this is the case, the cell damage can visibly accelerate aging and people become more susceptible to diseases such as Alzheimer's, arteriosclerosis or even cancer. However, to a certain extent, our bodies can handle this stress without any problem(1).


In the tissues of older people, a particularly large number of such damages and free radicals can be found. (Image source: Bruno Aguirre / Unsplash)

But: Adequate numbers of free radicals are also important for the body. These are used as agents of the immune system against foreign substances. Bacteria and viruses are attacked and pathogens are destroyed.

Therefore, a balanced balance of free radicals and radical scavengers in the human body is particularly important. As a result, your body can continually replenish its own defense system and fend off free radical attacks.

What are the different types of antioxidants?

Antioxidants are not just antioxidants. These occur in different compounds such as vitamins, polyphenolic antioxidants and carotenoids:

antioxidant main effect
vitamin C Boosting the immune system and reducing fatigue
vitamin E skin care

Antioxidants ensure a reduced risk of disease.

Nevertheless, one should not consume too many antioxidants unnecessarily, since the amount of antioxidants in the body cannot be measured clearly and reliably. It is not possible to say exactly when these can become "unhealthy"(3). Consequently, it cannot be ruled out that antioxidants also have negative consequences. In some cases, the desired results are not achieved in some treatments of cancer patients(4).

The fact is: many more clinical studies have to follow in order to create more clarity and certainty.

How can I get antioxidants?

Actually, there are only two ways to take antioxidants:

Balanced and healthy diet

Diet, apart from antioxidants, should have an important role in a person's life. Antioxidants are found in vitamin C in particular and this is often located directly under the peel, which is why you should eat the peel as much as possible. In addition to fruits and vegetables, whole grains, legumes, high-quality vegetable oils, and nuts are high in antioxidants(5).

Other benefits of a balanced and healthy diet include:

  • Good mood
  • Weight loss (if desired)
  • increase of productivity
  • Better complexion
  • Less tired

Nevertheless, you can also sin and reach for chocolate without having to fear that this will already have negative consequences for your health. The number of antioxidants will not drop rapidly either.

fruit and vegetables

A healthy and balanced diet consisting of fruit and vegetables also plays an important role when it comes to "antioxidants". (Image source: Jo Ma / unsplash)

With a balanced and healthy diet, it is no longer necessary to take food supplements because you are consuming enough antioxidants.

  • increase in quality of life
  • body is fitter
  • increase in motivation
  • Preparation often time-consuming
  • expensive
  • dietary supplements

    Sometimes it can also be very useful to use a dietary supplement. For example, if you are very stressed and don't eat well enough or if you do a lot of sport. Your immune system can be better supported and you don't have to worry about not taking enough antioxidants(6,7).

    dietary supplements

    Dietary supplements should never completely replace a balanced and healthy diet. (Image source: Mika Baumeister / unsplash)

    In general, doctors disagree on the use of dietary supplements. Before you buy, you should ideally talk to your doctor to get a medical assessment of the need. In the following we have put together a general table with pro and contra arguments on the subject of "dietary supplements yes/no".

    • easily accessible and easily ingestible
    • rich in antioxidants
    • Supplying active athletes with important nutrients
  • Feeling of complete food replacement arises
  • Interactions often insufficiently clarified
  • unclear dosages
  • Which foods contain the most antioxidants?

    The best way to get antioxidants is through food. To give you an overview of the foods that contain a lot of antioxidants, we have put together an overview:

    Groceries antioxidant Effect (besides antioxidant process)
    Coffee polyphenol Anti-inflammatory and cancer preventive
    nuts vitamin E Reduce oxidative stress
    Apple vitamin C Strengthens the immune system
    tomatoes carotenoid cancer prevention
    beef zinc Cell growth and immune defense

    Of course, these are just a few examples or inspirations. In the end, it is important that you make your diet varied and thus take in all the important nutrients. In addition, many delicious recipes with a particularly high proportion of antioxidants can be found on the Internet.

    What should I be aware of when using antioxidant supplements?

    In short: the dosage.

    As always, it is important to avoid overdosing. It is important to find a healthy balance between free radicals and antioxidants, both of which are important functions in the human body. Negative consequences arise when one of the two is present in a (much) larger amount than the other.

    The scientific community is still debating the effectiveness/use of supplements that help boost the immune system and increase antioxidant levels(8). However, countless dietary supplements can be found in pharmacies. Therefore, you should use such dietary supplements with caution and only with prior consultation with your doctor.

    Suggested maximum safe levels in dietary supplements per day:

    The same applies here: If you are unsure, it is better to contact a doctor. Otherwise, here are some recommended maximum daily amounts of various supplements that should not be exceeded(9):

    dietary supplements Maximum amount (per day)
    vitamin C 250 milligrams
    vitamin E 30 milligrams
    beta-carotene 0
    Secondary plant substances (anthocyanins, bioflavonoids, resveratrol) Doesn't exist

    You should be very well informed, especially when taking secondary plant substances as dietary supplements, as it is difficult to determine a generally recommended maximum amount. As with most other things in life, the same applies here: Better to ask once more.

    How can I get antioxidant supplements?

    Nowadays there are more and more suppliers of dietary supplements with antioxidants. You absolutely must inform yourself extensively before making a purchase, as many dietary supplements are available without a doctor's prescription. Also, be aware of the maximum amount you should be consuming each day. Just make sure the supplements are high in the following ingredients:

    • vitamin C
    • vitamin E
    • zinc
    • selenium
    • carotenoid

    You should therefore always pay attention to the ingredients when choosing a suitable dietary supplement. In principle, you will find what you are looking for in pharmacies, drugstores and supermarkets as well as on the Internet. When ordering dietary supplements over the Internet, you should definitely be particularly attentive, careful and critical, as there are always "black sheep" there (10).

    Of course, foods high in antioxidants are even better than dietary supplements. You can find these in almost every conventional supermarket. A trip to the weekly market is also recommended, where you will probably find even fresher fruit and vegetables.

    What do these cost?

    There is no definitive answer to this as antioxidant intake can come in a variety of forms. In addition, depending on the manufacturer, different quantities are offered at different prices.

    An example: When buying 250 milliliters of vitamin C in the form of food supplements, a price of around 18 to 25 euros can be expected.

    What happens if I take too many supplements?

    First of all: no need to worry!

    As long as you haven't consumed three times the reference value, there is no need to panic. Nevertheless, you should never exceed the daily amount, as there are not enough studies in this area. Smokers, for example, should be careful with the additional intake of beta-carotene, as ingestion could promote the development of lung cancer(11).

    dietary supplements

    The following still applies: Taking antioxidants in the form of dietary supplements should not be a substitute for your healthy diet! (Image source: unsplash / Diana Polekhina)

    Taking too much vitamin D can cause nausea and pain, among other things. In general, the risk of severe symptoms after taking too many antioxidants in the form of dietary supplements is low, but it is never impossible for your body to react badly to them (12).

    "Up to three times the reference value, we can assume that we are safe. Anything beyond that is a gray area" - Hans Konrad Biesalski, Professor of Biological Chemistry and Nutritional Science, University of Hohenheim


    Antioxidants protect our body from free radicals, which is why they are of great importance for our organism. These offer us protection against early cell aging, diseases and general cell decay. At best, people are already consuming enough antioxidants through a balanced and healthy diet with enough fruit and vegetables, so that the use of special dietary supplements is no longer necessary.

    Key antioxidants include vitamin C, vitamin E, caroline, and phytochemicals of all kinds. While the wrong dosage of supplements isn't too bad, it's still best to consult a doctor to find a dosage that's right for you. A balanced balance of free radicals and radical scavengers in the human body is particularly important.


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