Oxygen is an essential element for life, we cannot live without it, but it causes derivatives to be formed in the body that cause damage to our cells every day. These derivatives are called Reactive Oxygen Species and include free radicals. The purpose of antioxidants is to neutralise these free radicals.
What are free radicals?
In order to produce energy from the nutrients we eat, the body needs oxygen. This need leads to consumption of oxygen, which is not 100% efficient. A small proportion escapes (2-5%) and forms free radicals.
Free radicals can also be formed as a result of inflammatory reactions in the body or in the fight against toxic substances (pollution, tobacco, alcoholic beverages, etc.)
Athletes tend to produce a greater quantity of free radicals due to increased oxygen consumption and possible chronic inflammation.
How does the body react?
Free radicals are molecules that attack surrounding tissue. In the long term and in the event of chronic exposure, these changes promote the development of age-related diseases such as cardiovascular diseases, cancer, etc.
To combat the production of free radicals and in order to limit their concentration in our cells, the body has set up a defence system to neutralise free radicals: antioxidants.
There are two types of antioxidant:
- Antioxidants produced by the body (antioxidant enzymes)
- Antioxidants provided by the diet (vitamins C and E, carotenoids, etc.)
Diet plays an essential role in the fight against free radicals.
Free radicals: are they good or bad for the body?
Free radicals are not always harmful for the body. They help fight infections, eliminate cancer cells and stimulate production of antioxidants. For athletes, they allow energy production in cells to be adapted and improved. Free radicals are both beneficial and harmful, what is important is the balance between free radicals and antioxidants.
Main dietary antioxidants
Antioxidants are found in many different foods and primarily in plants, which produce many varieties to protect themselves from external damaging factors: the sun, impacts, etc. Antioxidants are mainly found in the skin and rind of plants, because they are the parts that are the most exposed to external factors.
What are some good sources of antioxidants?
Vitamin C: citrus fruits, blackcurrant, guava, papaya, kiwi, parsley.
Vitamin E: wheat germ oil, rapeseed oil, sunflower oil, walnuts, hazelnuts.
Carotenoids: Raw curly kale, raw spinach, raw carrots, sweet potato, raw tomatoes.
Selenium: Brazil nuts, wheat bran, oysters, sunflower seeds.
Zinc: Oysters, wheat germ, pumpkin seeds.