What Are Antioxidants? How They Work & Their Benefits

Published on March 13, 2023

By Kristen Boye BS, Natural Health

Kristen Boye

Kristen Boye is a natural health expert, writer, copywriter, and editor. Kristen was raised on an organic farm in British Columbia which inspired her life’s work. She holds a Bachelor’s Degree in Natural Health, is a Certified Natural Foods Chef, co-owner of a medicinal herb farm, and is a natural foods and children’s health advocate. Kristen lives with her husband and two children on their medicinal herb farm in Western North Carolina.

As a health-conscious person, you’ve likely heard about antioxidants and how they may benefit health and beauty.

But, if you’re unclear on exactly what an antioxidant is, how they work, and/or if you need to consume more of them, you are not alone.

In this article, you’ll learn everything you ended to know about antioxidant basics, including:

  • What are antioxidants?
  • The best sources of antioxidants
  • The potential science-backed benefits
  • The scoop on antioxidant supplements, including herbs
  • And the best way to get a healthy dose of antioxidants safely

    What Are Antioxidants?

    Antioxidants are molecules found within the body and in nature that delay cell damage by scavenging free radicals.REF#882

    • Antioxidants made within the body are called endogenous antioxidants. 
    • Antioxidants outside the body, such as in foods or the environment, are called exogenous or dietary antioxidants. 

    Both types are required to maintain optimal health and balance.REF#883

    Free radicals are unstable atoms missing an electron. 

    As they seek to replace their missing electron, they can cause damage to cells by creating oxidation, also known as oxidative stress.REF#884

    The oxidation effects of free radicals on cells are similar to the browning of an apple or pear after being cut or metal rusting. 

    If left unchecked, oxidative stress from free radical damage can cause cell damage and has been linked to various ailments such as aging, cognitive decline, heart disease, and other inflammatory issues.

    Where do Free Radicals Come From?

    Free radicals are created by everyday activities, such as exercise or your body breaking down foods. They can also be generated due to environmental factors like air pollution, poor diet, or smoking.

    Free radicals serve beneficial purposes in small amounts, such as participating in immune response, heart function, and detoxification.REF#885 REF#886 

    In other words, free radicals serve a functional purpose.

    They only become problematic in excess—often due to environmental and lifestyle factors—and that’s where antioxidants come in.

    What Are The Best Sources Of Antioxidants?

    Although many of us have been led to believe special pills or foods are required to get antioxidants, they exist all around us and even within us.

    Antioxidants can be found in: REF#887 REF#888 REF#889 REF#890 

    • Our bodies: Glutathione, MSM, and Melatonin, for example, are exogenous antioxidants manufactured in the body.
    • Plants: Such as brightly colored fruits, vegetables, and herbs. 
    • Foods: Including grains, meat, legumes, nuts, seeds, dairy products, spices, cocoa, and others. 
    • Beverages: Such as red wine, juices, teas, coffee, and antioxidant-enriched beverages.
    • Supplements: Like vitamins, minerals, herbs, and antioxidant-specific supplements such as Quercetin, Resveratrol, and others.
    • The environment: The earth (soil, water, rain) produces negative electrons that act as antioxidants.

    Some food sources are indeed richer in antioxidants than others.

    The following is a list of foods that are high in antioxidants:

    As you can see, brightly colored fruits and vegetables contain higher levels of certain antioxidants like Quercetin, vitamin C, oligomeric proanthocyanidins, flavonoids, and/or Resveratrol.

    But fruits and vegetables aren’t the only sources of antioxidants.

    Grass-fed meats and dairy products have been shown to have higher levels of certain antioxidants, such as conjugated linoleic acid and vitamin E, than conventionally-raised meats.REF#896

    Whole grains, such as oats, contain a potent mix of antioxidants, including selenium, polyphenols, and a type of antioxidant almost exclusive to oats known as Avenanthramides.REF#897

    Unique Antioxidant Compounds of Specific Herbs 

    Turmeric, for example, is a unique source of the antioxidant group curcuminoids, including Curcumin,REF#898 which has demonstrated numerous potential health benefits, including promoting heart health,REF#899 REF#900 weight management, REF#901 REF#902 joint health,REF#903 REF#904 and more.

    Many of Ashwagandha’s demonstrated health benefits, such as thyroidREF#905, sleep REF#906, and mood support REF#907, have been linked back to antioxidants within its withanolide groups of plant compounds.REF#908

    Bilberry contains anthocyanins, a major group of flavonoid antioxidants that support various aspects of well-being, such as vision, heart health, and inflammatory response.REF#909

    And Maca has been shown to contain polysaccharides, which may support and enhance the body’s antioxidant levels.REF#910

    The big takeaway: The best way to optimize your antioxidant intake is to eat a balanced, whole-foods-based diet with plenty of colorful fruits, vegetables, herbs, whole grains, and healthy proteins (and maybe a little dark chocolate on the side).

    What About Antioxidant Supplements? Are They Helpful Or Necessary?

    Research has shown the best way to get antioxidants is from food.REF#911

    That’s because isolated antioxidants, such as those in supplements, do not contain all the other nutrients, plant compounds, and other antioxidants you’d get from eating the whole food.

    For instance, whole berries contain the antioxidant vitamin C. They also contain polyphenols, fiber, minerals, polysaccharides, oligomeric proanthocyanins, Quercetin, Resveratrol, enzymes, and countless other phytochemicals designed to interact together for maximum absorption, assimilation, and benefit.

    That said, there is evidence antioxidant supplements can provide specific benefits for some concerns.

    Green Tea and Green Tea Extract, for example, provide a wealth of antioxidants without requiring the consumption of the leaves.REF#912

    And herbal supplements can also provide specific antioxidant benefits.

    Additionally, there is evidence that some antioxidant supplements, such as Quercetin,REF#889 Resveratrol,REF#913 Vitamin C,REF#914 Vitamin E,REF#915 Selenium,REF#916 and Green Tea extracts,REF#912 for example, can support cell health, heart health, histamine response, thyroid health, and various aspects of well-being.

    Evidence also shows that excess consumption of isolated antioxidants, such as Vitamins C and E, can cause free radical damage.REF#917 REF#918 

    Ultimately, a healthy and diverse plant-based diet is the best way to ensure you get plenty of antioxidants.

    However, a supplement may be beneficial if you’re dealing with specific health challenges or have certain health goals.

    If you’re unsure, talk to your doctor or integrative health practitioner.

    Tips On Getting Enough Antioxidants In Your Diet

    • Aim for at least 5-7 servings of fruits and vegetables daily (the more, the better).
    • Eat the rainbow! Remember, the more brightly colored the fruit or vegetable, the more antioxidant power it has.
    • Don’t rule out whole grains, such as oats and quinoa, as a good source of antioxidants.
    • If you eat meat, consider grass-fed meats and wild-caught fish for greater antioxidant content.
    • Consider including various wild mushrooms in your diet and/or as a supplement.
    • Take advantage of the earth’s negative electron antioxidants by walking barefoot, gardening, and swimming in natural water.
    • Make herbs and spices a part of your life. Whether used in cooking or as a supplement, herbs are an excellent natural source of antioxidants.

    Gaia Herbs has several formulas that contain plant-based antioxidants in their whole, natural form. Some best-sellers include:

    For help getting more antioxidant-rich foods into your diet, check out these antioxidant-inspired recipes, including antioxidant-rich foods, herbs, and spices. Including:


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