What are antioxidants and what are they for?

You've probably heard of the antioxidants that some foods contain, but, Do you know exactly what antioxidants are and what they are for?, in this article you will solve all your doubts.

Antioxidant intake is essential to maintain good health.. Their role as oxidative stress reducers is what has made them so fashionable.

What are antioxidants?

Antioxidants they are compounds synthesized by vegetables in their different parts, as fruits, leaves, branches, roots, etc. They are characterized by hydroxyl groups (OH) linked together by benzene rings, which prevent the damaging effect of free radicals.

What are they for?

The antioxidants in food are essential, not only because they activate the natural organoleptic properties, but because, when ingested, they protect us from diseases such as cancer, cardiovascular diseases and neurodegenerative diseases.

Eat a diet rich in antioxidants It will help us to prevent and improve:

  • Premature aging, produced by the accumulation of free radicals.
  • Nervous system, as it has been shown to help prevent dementia, Alzheimer's and Parkinson's, thanks to a protective effect of neurons.
  • Cardiovascular diseases, such as atherosclerosis.
  • Cancer, since antioxidants can inactivate carcinogenesis, inhibit cell proliferation, improve DNA repair processes and reduce oxidative stress.

What is oxidative stress?

To know how antioxidants act, it is necessary to know what oxidative stress is. In cellular metabolism, in which glucose reacts with oxygen to produce energy in the form of ATP, the release of a series of reactive oxygen compounds occurs. These compounds are free radicals, whose effects are harmful to the body.

In a young and healthy individual, oxygen free radicals are quickly removed from inside the cell by natural antioxidants. But, in chronic patients or in the elderly, this elimination is deficient, which implies the appearance of chronic diseases, accelerating, at the same time, aging.

Also read: Diet to prevent aging, includes the following nutrients

Types of antioxidants

Antioxidants can be:

  • Endogenous
  • Manufactured by the cell itself.
  • Exogenous, that enter the body through diet or supplements with antioxidant formulations.

Here we will explain what are the most important antioxidants from food:

Vitamin C

It is an important antioxidant that acts enhancing the effect of other antioxidants, Just like with vitamin E and selenium.

The Principal functions of vitamin C are:

  • Neutralize singlet oxygen (O2).
  • Capture hydroxyl radicals and superoxide anions.
  • Regenerate the oxidized form of vitamin E.

This vitamin mainly contributes to the synthesis of collagen and elastin., essential components for the development and maintenance of blood vessels, tendons, bones and ligaments. In addition, it is crucial for the synthesis of norepinephrine and carnitine, and also in the transformation of cholesterol into bile salts.

Five daily servings of fruits and vegetables (3 fruits and 2 vegetables), ensure a minimum consumption of 200 mg of vitamin C. main sources of vitamin C They are:

  • Peppers.
  • Brussels sprouts.
  • Broccoli.
  • Tomato.
  • Kiwi.
  • Strawberries
  • Orange.
  • Lemon.

Vitamin E

It is a set of phenolic compounds, known as tocopherols and tocotrienols. Alpha tocopherol is the most common and, biologically, the one with the greatest vitamin action.

Vitamin E is considered the most important protector of lipid molecules, since Its action consists of:

  • Protect polyunsaturated fatty acids from oxidation of cell membrane phospholipids.
  • Inhibit the oxidation of LDL cholesterol (bad cholesterol)

The recommended dose of vitamin E ranges from 6 mg in children, to 15 mg in adulthood. It is present in foods such as olive, corn, soy, canola, safflower or sunflower oils. It is also present in the intake of small amounts of nuts such as almonds, peanuts, hazelnuts or nuts and in raw vegetables such as carrots and spinach.

It is interesting: Avitaminosis: the lack of vitamins


Polyphenols are a very large group of substances that include families of compounds with diverse structures. Only flavonoids, which are the most important, are known more than 5000 different compounds in nature.

Many phenolic compounds They are responsible for the organoleptic properties of vegetables. For example, anthocyanins are responsible for the red, blue and violet tones of many fruits, vegetables and red wine.

From the point of view of its biological activity, many polyphenols have properties:

  • Anti-inflammatory, since they inhibit enzymes and the C-reactive protein involved in the inflammation processes.
  • Estrogenic activity, such as isoflavones, lignans and resveratrol.
  • Fixation of metals and proteins, such as tannins, which gives them antimicrobial activity.

They are found in abundant fruits, vegetables, cereals and legumes, as well as some drinks and infusions, such as tea, coffee, red wine and cocoa.


They are pigments synthesized by plants in the process of photosynthesis whose main activity is the neutralization of reactive oxygen spices (ROS). These reactive species have a determining role in the development and maintenance of cellular oxidative stress.

Carotenoids are converted to vitamin A, whose role is essential to preserve the integrity of the retina and to maintain the activity of the immune system, among other things.

The foods that contain them They are:

  • Carrot.
  • Orange.
  • Peach.
  • Tangerine.
  • Tomato.
  • Watermelon.
  • Papaya.
  • Spinach.
  • Broccoli.

Thus, Do not forget to include varied fruits and vegetables in your diet daily. So, You can get all the antioxidants that your body needs.