Everything You Need To Know About Antioxidants

Various foods that are rich in antioxidants.

Antioxidants are essential compounds that protect our cells from damage and play a significant role in maintaining overall health.

Antioxidants are compounds that play an important role in maintaining various areas of our health by protecting our cells from damage. There are many different kinds of antioxidants — our bodies can produce them and they are found in many of the foods we eat. This article explains what antioxidants are and how they function in the body, and shares about the myriad benefits they offer. It also details how you can increase your family's antioxidant intake through food and supplementation.

What Are Antioxidants?

Antioxidants are molecules, and they are best known for their unique role in neutralizing free radicals (1). Antioxidants can be grouped into endogenous antioxidants and exogenous antioxidants (2). Endogenous antioxidants are antioxidants our body generates on its own. Endogenous antioxidants can exist as enzymes, such as catalase (CAT), or in non-enzyme forms, like bilirubin or uric acid. A well-known endogenous antioxidant is glutathione (2), which we will discuss more below. Exogenous antioxidants are antioxidants that the body can't produce on its own (2). This includes phytochemicals like flavonoids and polyphenols; trace elements like selenium, copper, zinc, and manganese; and vitamins C and E (2).

How Do Antioxidants Work?

The body needs to maintain a certain balance of free radicals and antioxidants (2). When free radicals outnumber antioxidants, it can lead to a state called oxidative stress (2). In order to understand how antioxidants work, it’s important to understand each of these processes.

What Are Free Radicals?

Because the main job of antioxidants is to neutralize free radicals (2), it is important to first understand what free radicals are and how they occur.

Free radicals are unstable atoms that can damage cells, leading to inflammation, aging, and diseases, such as cancer (3). Free radicals are produced naturally in the body as a byproduct of metabolism but can also result from external sources like pollution, tobacco smoke, and radiation (2). In short, free radicals are highly reactive molecules with unpaired electrons that cause cellular damage (3).

Antioxidants are molecules that can donate an electron to a free radical without becoming destabilized themselves and thereby neutralizing the free radical so that it can’t cause damage (2). This action prevents free radicals from causing harm to cells.

What Is Oxidative Stress?

When there is an imbalance between free radicals and antioxidants, oxidative stress occurs (4). Oxidative stress can damage cellular components, such as DNA, proteins, and lipids (5). This damage is associated with chronic diseases, such as cardiovascular disease, diabetes, and cancer, as well as the aging process (5).

Some antioxidants, such as vitamin C and vitamin E, can regenerate other antioxidants; this mechanism is usually referred to as the “antioxidant network” (6). For instance, when vitamin E neutralizes a free radical, it becomes oxidized itself. Vitamin C can then donate an electron to oxidized vitamin E, regenerating it back to its active form (6).

Antioxidants & Detoxification

Antioxidants are an important part of the body’s detoxification processes. The liver plays a central role in detoxification, breaking down harmful substances and preparing them for excretion. Antioxidants support this process in several ways.

Antioxidants Support Phase I and Phase II Detoxification

Detoxification processes can generate free radicals, leading to oxidative stress. Antioxidants help mitigate this stress by neutralizing free radicals, protecting the liver and other tissues from damage.

Detoxification occurs in two phases. In Phase I, toxins are converted into intermediate compounds and may release free radicals, which can sometimes be more harmful than the original toxins. Antioxidants, like vitamins C and E, help neutralize these intermediate compounds, reducing their potential damage (7).

In Phase II, the liver adds molecules to these intermediates, stabilizing free radicals and making other molecules water-soluble for excretion. Antioxidants such as selenium and flavonoids support enzymes involved in this phase, enhancing the body's ability to detoxify effectively (7).

If you would like to learn more about detoxification, read: How Does Detoxification Work? Understanding Phase I, Phase II, and Phase III Detoxification and 10 Ways To Support Detoxification In Kids

Sources of Antioxidants

To reap the benefits of antioxidants, it's essential to include a variety of antioxidant-rich foods in your diet. This can be done by eating a whole foods based varied diet.

Colorful Fruits and Vegetables

Incorporating a wide range of colorful fruits and vegetables into your meals provides a range of powerful antioxidants. Some examples include (8):

Red foods (tomatoes, strawberries) contain lycopene.
Orange and yellow foods (carrots, sweet potatoes) are rich in beta-carotene.
Green foods (spinach, kale) contain lutein and zeaxanthin.
Blue and purple foods (blueberries, eggplants) are rich in anthocyanins.

Whole Grains, Nuts, Seeds, & Legumes

Whole grains, nuts, seeds, and legumes are packed with antioxidants:

Whole grains (oats, quinoa) contain selenium and phenolic acids (9).
Nuts and seeds (almonds, sunflower seeds) are rich in vitamin E and selenium (10).
Legumes (beans, lentils) contain flavonoids and phenolic acids (11).

Various fruits and vegetables that are rich in antioxidants.

Quality Animal Products

It is a common misconception that antioxidants are only found in plants, when in actuality quality animal foods can be a good source of antioxidants as well.

Grass-fed beef and pasture-raised poultry contain higher levels of antioxidants, such as vitamin E and glutathione, compared to conventionally raised meat (12).
Organ meats, such as liver, are rich in Coenzyme Q10 (CoQ10) (13) and selenium (14), both powerful antioxidants.
Fatty fish, like salmon, mackerel, and sardines, are excellent sources of astaxanthin (15), a potent antioxidant found in marine environments.
Shellfish, such as oysters and mussels, provide zinc and selenium (16).
Eggs, particularly those from pasture-raised hens, are rich in antioxidants such as lutein and zeaxanthin (17).

Antioxidant-Rich Beverages

A great way to increase your antioxidant intake is by drinking them!

Green tea: Green tea contains catechins, which are powerful antioxidants (17).
Hot Cocoa: Cocoa is rich in flavonoids (18).
Golden Milk: Turmeric and ginger are rich in curcumin and gingerol (19).
Breast Milk: Breast Milk contains antioxidants, and research shows that mothers who consume more antioxidants have higher antioxidant levels in their milk (20).

Herbs and Spices

Many herbs and spices are rich in antioxidants. I like to buy culinary herbs and spices in bulk from my local health food store and keep them in my freezer to better preserve nutrients. I use the below herbs and spices liberally in my cooking for their delicious flavor and their antioxidant content (21), and I also utilize them in my herbal formulations and teas for their beneficial properties:

Turmeric: contains curcumin
Ginger: contains gingerol
Cinnamon: contains cinnamaldehyde
Oregano: contains rosmarinic acid
Basil: contains eugenol
Parsley: contains apigenin
Thyme: contains thymol
Peppermint: contains menthol
Sage: contains carnosic acid

Increasing Antioxidant Intake Through Supplementation

Mother nature has given us an abundance of antioxidant rich foods that can be incorporated into all kinds of diets. That said, sometimes supplementation can be a helpful addition to increase antioxidant intake.

When to Consider Antioxidant Supplementation

Individuals with specific health conditions, dietary restrictions, or increased oxidative stress may benefit from additional antioxidant support. For example, those with limited access to fresh fruits and vegetables, individuals recovering from illness or struggling with sleep, or people exposed to high levels of environmental pollutants may find antioxidant supplements especially beneficial.

If you’d like to learn more about choosing supplements for your family, please read: Choosing A Supplement Delivery Method For Your Family and How To Calculate Supplement Dosages For Kids

Types of Antioxidant Supplements

Common antioxidant supplements include:

Vitamin C: Vitamin C is perhaps the most common antioxidant supplement. Vitamin C is often supplemented to boost the immune system and support skin health. Vitamin C is a water-soluble vitamin, meaning that your body doesn't store it, and it needs to be regularly consumed for optimal levels (22).
Selenium: Selenium benefits the immune system and has powerful anti-aging properties thanks to its antioxidant properties (23).
Coenzyme Q10 (CoQ10): CoQ10 is a powerful antioxidant, it supports cellular energy production, and is beneficial for cardiovascular health (23).
Glutathione: Glutathione is produced by the body, but can become depleted (24). Glutathione is available in supplement form but is often not well absorbed (25). For this reason, glutathione precursor NAC is often a preferred supplement for those looking to increase glutathione levels (26). Milk thistle is an herb that contains the antioxidant silymarin, which is supportive of endogenous glutathione production (27).
Curcumin: Curcumin is often combined with piperine in supplements for increased bioavailability (28).

Is It Possible To Consume Too Many Antioxidants?

While antioxidants are essential for maintaining good health, it is possible to consume too many. It is very difficult to over consume antioxidants from food sources, so this is really only a consideration when it comes to excessive supplementation. For instance, high doses of vitamin E supplements have been linked to an increased risk of hemorrhagic stroke. Similarly, excessive selenium can lead to selenosis, a condition characterized by gastrointestinal disturbances, hair loss, and mild nerve damage. Consulting with a healthcare provider before starting any new supplement regimen is advisable to ensure it is appropriate for your individual health needs.

Summary

Antioxidants are essential compounds that protect our cells from damage and play a significant role in maintaining overall health. By neutralizing free radicals, they help prevent chronic diseases, reduce inflammation, and support the body's natural detoxification processes. Incorporating a variety of antioxidant-rich foods, such as colorful fruits and vegetables, whole grains, nuts, seeds, pasture raised animal products, and antioxidant-rich beverages, like green tea, can enhance your family's antioxidant intake. Additionally, using herbs and spices in your cooking can boost the antioxidant content of your meals. In certain situations, supplementation with antioxidants may be beneficial.

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