May 15, 2020

What Do Antioxidants Do?

If you follow the latest news in nutrition and healthy diet, you’ve undoubtedly been introduced to the concept of “superfoods” like blueberries, avocados, and mushrooms (1).

These superfoods contain vitamins and minerals that are important for the body and also are high in nutritional value, providing the energy our body needs to function, but they’re also frequently a source of another important substance, called antioxidants.

Everything from beauty creams to your daily multivitamin promises to come packed with antioxidants, but what exactly are antioxidants and what do antioxidants do?

What are Antioxidants?

Antioxidants, sometimes called “free radical scavengers,” are substances in the body that help slow or prevent cell damage caused by free radicals. Free radicals are unstable waste substances that are naturally produced by cells as a byproduct of processing food and reacting to the environment.

Although free radicals are naturally produced by the body, they can cause damage to the cell membrane or body functions if they cannot be processed and removed from the body efficiently. That’s where antioxidants come in!

What Do Antioxidants Do?

Antioxidants are free radical fighters that work to help the body process and remove free radicals before they cause harm. Our bodies actually need free radicals to perform functions like fight infections, but when there is an imbalance between free radicals and antioxidants, the body can experience a condition called oxidative stress (2).

Over a prolonged period of time, oxidative stress begins to damage the DNA and other molecules in the body and can cause cell death. As DNA becomes damaged, the risk of cancer also increases.

Oxidative stress has been linked to a number of serious health conditions, including heart disease, arthritis, respiratory diseases, emphysema, cancer, stroke, immune deficiency, Parkinson’s disease, and other inflammatory and ischemic conditions (3). 

When our bodies have the right balance between antioxidants and free radicals, we are able to stave off oxidative stress, helping to boost overall health.

What Other Factors Impact Free Radical Formation and Oxidative Stress?

We’ve established that free radicals are formed by natural processes of the body, but there are also other outside factors that influence the excessive formation of free radicals, leading to higher rates of oxidative stress.

Our environments play a huge role in the formation of free radicals in our bodies, especially exposure to things like air pollution, toxins, cigarette smoke, radiation or frequent exposure to sunlight, and more.

Other factors, including lifestyle, can also play a role in the development of free radicals, including alcohol intake, stress levels, high blood sugar levels, bacterial, viral, or fungal infections, too much iron, magnesium, copper, or zinc in the body, inappropriate levels of oxygen in the body, intense or lengthy exercise that causes tissue damage, and high intake of polyunsaturated fats.

People with many of these risk factors are especially at risk for the development of oxidative damage.

What are Common Sources of Antioxidants?

Clearly, having enough antioxidants is critical to overall health and avoiding oxidative damage, but where do antioxidants come from? Antioxidants come from both natural and artificial sources.

Most commonly, antioxidants are found in certain plant-based foods, like fruits and greed leafy vegetables. When found in plants, antioxidants are considered a phytonutrient, or a plant-based nutrient. Because all animals have their own methods of eliminating free radicals from their bodies as well, animal products like meat also contain antioxidants, although in lower quantities than fruits and vegetables.

Some antioxidants are also produced by the body in the form of endogenous antioxidants, meaning they originate from inside the body. Exogenous antioxidants are those that originate outside the body. 

What Are Common Antioxidants?

People who aren’t familiar with antioxidants may think they have never heard of a single antioxidant before, but that’s most likely not the case. The term “antioxidants” is actually a phrase that describes the actions of a group of substances. Common antioxidants that you may be familiar with include:

  • Vitamin A
  • Vitamin C
  • Vitamin E
  • Lycopene
  • Selenium
  • Astaxanthin
  • Zeaxanthin
  • Beta-carotene
  • Lutein
  • Manganese

Some of the lesser known antioxidants include flavonoids, catechins, phytoestrogens, flavones, and polyphenols, all of which are found in plant foods.

How Do I Know If I’m Getting Enough Antioxidants?

Think back to what you’ve eaten over the past week. Have you been averaging the recommended four servings of fruits and five to six servings of vegetables per day? Am I taking an antioxidant-rich vitamin?

If not, you’re probably not getting enough antioxidants, which is the situation most Americans find themselves in. 

What Foods are Highest in Antioxidants?

If, like most people, you suspect you’re not taking in enough antioxidants or you’re looking for an excuse to make the shift towards a more plant-based healthy diet, the ease with which you’ll find antioxidant-rich foods is one great reason to incorporate more fruits and green leafy vegetables into your diet.

Some antioxidants, like vitamins C and E, are actually critical to our physical survival. Without them, our bodies can’t function. Other antioxidants won’t necessarily cause death if they are absent from your diet, but you will notice a major decline in your health. Sources of specific antioxidants include:

  • Vitamin A: 

Sweet potatoes, winter squash, kale, liver, eggs, dairy products

  • Vitamin C: 

Many fruits and vegetables, especially citrus, berries, and bell peppers

  • Vitamin E:

Leafy green vegetables, nuts and seeds, sunflower and other vegetable oils

  • Lycopene: 

Tomatoes, watermelon, and other pink and red fruits and vegetables

  • Selenium: 

Rice, wheat, corn, whole grains, nuts, cheese, eggs, and legumes

  • Astaxanthin: 

Algae, shrimp, lobster, crab, and salmon

  • Zeaxanthin: 

Leafy green vegetables and other green and yellow vegetables

  • Beta-carotene: 

Fruits and vegetables with bright colors, like spinach, mangoes, peas, and carrots

  • Lutein: 

Corn, oranges, papaya, and leafy green vegetables

  • Manganese: 

Nuts, legumes, whole grains, leafy green vegetables, sweet potatoes


If you’re interested in finding foods that are good all-around sources of antioxidants rather than focusing on your intake of specific vitamins and minerals, the trick is to look for antioxidant rich foods with vibrant colors, as these are usually packed with antioxidants. Examples include:

  • Blueberries
  • Broccoli
  • Apples
  • Spinach
  • Lentils
  • Pomegranates
  • Red grapes
  • Eggplant
  • Goji berries

Of course, dietary restrictions and limited access to fresh produce can add major challenges when it comes to making sure you’re getting enough antioxidants.

While your first instinct might be to head to your local pharmacy and grab a generic multivitamin, it’s important to know that antioxidants are best absorbed and used by the body when they’re ingested as food.

If finding antioxidant-rich foods is challenging, real food vitamins like GEM are packed with the essential nutrients your body needs, all derived from real plant food with no fillers, additives, or chemicals. 

By the Digits

6,000: the number of known flavonoids-- and that’s just  a single category of antioxidants (4).


>3,100: the number of foods tested in a single study for total antioxidant content (5).


261.5 mmol/100 g: the average antioxidant content of Indian Gooseberry; berries are berry products are relatively high in antioxidant count (5).


0.16 mmol/100 g: the average antioxidant content of egg yolks; eggs are nearly void of antioxidants, and most are found within the yolk (5).


79%: the percent of antioxidants that come from beverages (such as coffee and wine) in the standard Western diet (6).

Do Antioxidants Affect Aging?

You know that having an imbalance of free radicals and antioxidants can lead to oxidative stress, which can contribute to some serious health conditions, but you may not have considered that a lack of antioxidants can also contribute to premature aging.

When the body is under oxidative stress due to an excess of free radicals, molecules and cell membranes that are damaged or destroyed by free radicals are forced to regenerate sooner than it otherwise would have, thereby accelerating the aging process.

Studies suggest that free radicals do play a role in the aging process and that the antioxidant levels in individuals can impact how frequently they experience age-related diseases and their overall health (7). While making sure you get enough antioxidants won’t necessarily turn the clock back twenty years, it can help make sure that you don’t age faster than you otherwise would.

Does It Matter Where I Get My Antioxidants?

You might think that adding antioxidants to your diet in the form of a multivitamin pill from your local pharmacy would be helpful and even necessary to maintaining good health, but the research actually shows that sometimes these unnatural antioxidant supplements do more harm than good.

Excessive levels of antioxidants intake have been linked to increased risks of certain cancers, including lung cancer in smokers with a high intake of beta-carotene and prostate cancer in people with a high dose of vitamin E (8).

Research shows that health problems resulting from antioxidants are linked to artificial sources, so it’s important to get your antioxidants naturally whenever possible by eating a healthy balanced diet full of fruits and vegetables or taking a real food plant-based vitamin like GEM

Bottom Line

Antioxidants are critical substances that our body needs to help prevent cellular damage, carry out important bodily functions, and prevent premature aging.

In addition to influencing our environment and shifting our lifestyles as best we can to prevent outside sources of free radicals from infiltrating our bodies, eating a healthy, balanced diet full of fruits and vegetables and adding a real-food plant-based vitamin can help ensure our bodies have all the antioxidants they need to live the long, healthy lives we all desire. 











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