Antioxidants: What Are They and What Are They For?

Antioxidants are substances capable of neutralizing the formation of free radicals and improving the state of health. Learn more.
Antioxidants: What Are They and What Are They For?
Saúl Sánchez

Written and verified by el nutricionista Saúl Sánchez.

Last update: 12 May, 2023

Antioxidants are a group of substances present in food that, despite not having a nutritional function, have an essential role in promoting health. They’re involved in multiple reactions that take place daily in the body, neutralizing the waste by-products that are generated.

There are many different antioxidants. Most of them are present in foods of plant origin. The body is also capable of synthesizing some endogenously, as a means of fighting aging.

What is the function of antioxidants?

These substances, as their name indicates, are responsible for balancing the oxidation and reduction processes that take place daily inside the body. They’re capable of donating an electron to reactive oxygen species that are formed from metabolic reactions. In this way, the atoms become much more stable.

It must be borne in mind that oxidation is a process closely linked to inflammation. The latter, in turn, is capable of increasing the incidence of several complex diseases, according to a study published in Current Topics in Behavioral Neurosciences.

An example would be the cardiovascular type. Inflammation affects the risk of thrombus formation and makes it difficult for blood to flow through the blood vessels.

Antioxidant Benefits

As we indicated, the regular intake of antioxidants is capable of reducing the number of waste metabolites that accumulate in the tissues. Among them are free radicals, which are reactive oxygen species with a mutagenic capacity. These pose a danger to cell replication and their uncontrolled presence has shown carcinogenic capacity.

In this way, the regular consumption of antioxidants is capable of helping in the prevention of tumors. At the same time, it can control the oxidation processes of the LDL lipoprotein, which translates into a lower cardiovascular risk.

There’s evidence that the contribution of this type of substance has a positive impact on the functioning of the heart and on the transport of nutrients through the blood.

A stethoscope sitting by a heart-shaped bowl with antioxidant sources
Antioxidants have the ability to improve heart function in the long term and prevent premature aging.

Where to find them?

Antioxidants are found in foods from the plant kingdom. Most of them are nothing more than pigments responsible for providing color to the products.

Some vitamins can also act as antioxidants, the most representative of this group being vitamin C, which can be found in peppers, strawberries, and citrus fruits.

In any case, the organism can synthesize some elements that carry out this function. Among all of them, we’ll mention glutathione, which is also a substance present in various foods. This compound balances the oxidation and reduction processes that take place internally.

Antioxidant Supplements

Due to the beneficial effects of antioxidant consumption, some authors propose supplementation with them to enhance their functions. In this regard, dietary supplements have been developed where phytonutrients are isolated. The most common are curcumin, anthocyanins, and N-acetylcysteine.

The ability of these supplements to reduce the incidence of many complex diseases, such as neurodegenerative ones, has been demonstrated. At the same time, there’s a consensus that they could stimulate lipid oxidation, which has a positive impact on the individual’s body composition.

However, antioxidant supplementation isn’t beneficial in all settings. Within the framework of intense exercise, the consumption of these elements in large amounts could interfere with cell signaling pathways, which would prevent subsequent muscular adaptations. This is a problem in terms of increasing performance.

Antioxidants and cancer

One of the priority objectives of the consumption of antioxidants is the prevention of cancer. As we’ve discussed, free radicals that accumulate in tissues can increase the risk of mutations, which cause tumors.

However, its use in large doses is also proposed once the carcinogenic process has been detected. Apparently, this type of element can improve the effects of chemotherapy, reducing the rate of progression and tumor division.

Therefore, life expectancy could be increased with adequate dietary intervention. The most studied for this purpose are anthocyanins and curcumin, as well as some phytonutrients present in cruciferous vegetables. Vitamin C in very high doses also has beneficial effects in these cases.

What’s the best antioxidant?

Many people wonder what the most powerful or effective antioxidant is. In this regard, there are many doubts. At present, no organized list of antioxidants according to their potential has been elaborated.

We can define that the nutrients present in cruciferous vegetables are especially beneficial for the prevention of complex respiratory diseases. Curcumin has potential in the treatment and prevention of tumors linked to the liver. Tomato lycopene, for its part, generates a positive effect on the functioning of the cardiovascular system.

As each one of them has specific functions and certain target tissues, it’s a good idea to combine them in the dietary regimen. This is another reason why a good diet must be based on the variety of foods included.

Vegetables in the diet guarantee the consumption of antioxidants

As discussed, it’s essential to include vegetables in the diet to guarantee the intake of antioxidants. Both fruits and vegetables contain this type of compound with beneficial properties. Culinary spices are also sources of antioxidants, so it’s a good idea to use them as much as possible for the preparation of dishes.

In the event that the diet is restrictive in a certain food group, for whatever reason, supplementation may be considered. However, this determination must first be consulted with a nutrition professional. There are different types of supplements on the market and it’s important to acquire one that meets the established expectations.

In any case, keep in mind that increasing the intake of fresh products and reducing ultra-processed ones will be a point in favor when it comes to guaranteeing a correct consumption of antioxidants. The latter have additives and trans fats capable of increasing oxidative processes and the formation of waste compounds.

A table full of fruits, vegetables, and grains.
The inclusion of vegetables in the diet is the fundamental step to ingesting various antioxidants.

Habits that reduce oxidation

In addition to the consumption of antioxidants, there are other lifestyle habits that are capable of reducing oxidation in the body, as well as inflammation. One of them is the practice of physical exercise on a frequent basis. This routine causes the maintenance of adequate body weight.

At the same time, it’s essential to guarantee good rest. During the hours of sleep, many of the processes that have a recuperative nature take place. In addition, a neurohormone, melatonin, which has high antioxidant capacities, is synthesized.

Besides, it’s worth noting the importance of avoiding stress. Anxiety situations increase the production of the hormone cortisol, which is associated with a greater synthesis of reactive oxygen species in the tissues. This condition favors oxidation and the appearance of premature aging.

Antioxidants: Important and essential substances

As you’ve seen, antioxidants are substances present in food that have a fundamental impact on health. Their adequate consumption can prevent the appearance of many chronic and complex diseases. For this reason, their regular presence in the diet is recommended.

Plant-based foods are those with the highest content of this type of substance, which are often the pigments responsible for giving them color. However, they can also be synthesized endogenously in the body.

There’s always the option of supplementing with antioxidants. However, it isn’t a recommended option for everyone or for all cases. It has application frameworks and limitations, so we always recommend consulting a nutrition professional before making a decision of this type.

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