Every one of us has both free radicals and antioxidants present inside of our bodies at all times. Some antioxidants are made from the body itself, while we must get others from our diets by eating high-antioxidant foods that double as anti-inflammatory foods.
Our bodies also produce free radicals as byproducts of cellular reactions. For example, the liver produces and uses free radicals to detoxify the body, while white blood cells send free radicals to destroy bacteria, viruses and damaged cells.
When certain types of oxygen molecules are allowed to travel freely in the body, they cause what’s known as oxidative damage, which is the formation of free radicals. When antioxidant levels in the body are lower than that of free radicals — due to poor nutrition, toxin exposure or other factors — oxidation wreaks havoc in the body.
The effect? Accelerated aging, damaged or mutated cells, broken-down tissue, the activation of harmful genes within DNA, and an overloaded immune system.
The Western lifestyle — with its ultra-processed foods, reliance on medications, and high exposure to chemicals or environmental pollutants — seems to lay the foundation for the proliferation of free radicals. Because many of us are exposed to such high rates of oxidative stress from a young age, we need the power of antioxidants more than ever, which means we need to consume antioxidant foods.
What Are Antioxidants?
What is an antioxidant, and why is it important? While there are many ways to describe what antioxidants do inside the body, one antioxidant definition is any substance that inhibits oxidation, especially one used to counteract the deterioration of stored food products or remove potentially damaging oxidizing agents in a living organism.
Antioxidants include dozens of food-based substances you may have heard of before, such as carotenoids like beta-carotene, lycopene and vitamin C. These are several examples of antioxidants that inhibit oxidation, or reactions promoted by oxygen, peroxide and/or free radicals.
Antioxidants also help neutralize harmful free radicals to prevent the potential negative effects on health. Free radicals accumulate in the body due to oxidative stress, which can be caused by a number of different factors, including diet and lifestyle. Over time, free radicals can cause cell damage and contribute to the development of chronic disease.
Why are antioxidants good for you? Research suggests that when it comes to longevity and overall health, some of the benefits of consuming antioxidant foods, herbs, teas and supplements include:
- Slower signs of aging, including of the skin, eyes, tissue, joints, heart and brain
- Healthier, more youthful, glowing skin
- Reduced cancer risk
- Detoxification support
- Longer life span
- Protection against heart disease and stroke
- Less risk for cognitive problems, such as dementia
- Reduced risk for vision loss or disorders, like macular degeneration and cataracts
- Prevention of oxidation and spoilage
The term “antioxidant” doesn’t actually refer to one specific compound but rather the activity of specific compounds in the body. There are many different types of antioxidants, including several antioxidant vitamins, minerals and polyphenols.
Most whole foods include a mix of the best antioxidants, making it easy to maximize the potential health benefits and fit a range of vitamins for the immune system into your diet.
Along with other compounds on the list of antioxidants, vitamin C antioxidants are highly effective at neutralizing free radicals to protect against disease. Other vitamins and minerals that have powerful antioxidant properties include vitamin A, vitamin E, manganese and selenium.
1. Slow the Effects of Aging by Reducing Free Radical Damage
As described above, the single most important benefit of antioxidants is counteracting free radicals found inside every human body, which are very destructive to things like tissue and cells. Free radicals are responsible for contributing to many health issues and have connections to such diseases as cancer and premature aging of the skin or eyes.
The body uses antioxidants to prevent itself from the damage caused by oxygen. Electrons exist in pairs; free radicals are missing an electron. This is their weapon of sorts. They “react” with just about anything they come into contact with, robbing cells and compounds of one of their electrons.
This makes the effected cell or compound unable to function and turns some cells into “electron-seeking muggers,” leading to a chain reaction in the body and the proliferation of free radicals. Free radicals then damage DNA, cellular membranes and enzymes.
2. Protect Vision and Eye Health
The antioxidants vitamin C, vitamin E and beta-carotene have all been shown to have positive effects on preventing macular degeneration symptoms, or age-related vision loss/blindness. Many foods that provide these nutrients also supply antioxidants called lutein and zeaxanthin, nicknamed the eye vitamins, found in brightly colored foods like fruits and vegetables — especially leafy greens and types that are deep orange or yellow.
These antioxidants are believed to be easily transported around the body, especially to the delicate parts of the eyes called the macula and the lens. In fact, there are more than 600 different types of carotenoids found in nature, but only about 20 make their way into the eyes.
Of those 20, lutein and zeaxanthin are the only two (macular carotenoids) that are deposited in high quantities into the macular portion of the eyes, which is one of the earliest to be damaged during aging. Research shows that high-lutein sources like spinach are proven to help decrease eye-related degeneration and improve visual acuity.
Similarly, flavonoid antioxidants found in berries, such as bilberries or grapes (also great sources of the antioxidant resveratrol), may be especially beneficial at supporting vision into older age.
3. Reduce the Effects of Aging on the Skin
Perhaps most noticeably, free radicals speed up the aging process when it comes to the appearance and health of your skin. Using antioxidants for skin may help combat this damage, especially from eating sources high in vitamin C, beta-carotene and other antioxidants.
Vitamin A and C have been connected to a decrease in the appearance of wrinkles and skin dryness. Vitamin C, specifically, is a powerful antioxidant that can help reduce the effect of oxidative damage caused by pollution, stress or poor diet.
Vitamin A deficiency has also been linked to skin dryness, scaling and follicular thickening of the skin. Similarly to how free radicals damage surface skin cells, keratinization of the skin, when the epithelial cells lose their moisture and become hard and dry, can occur in the mucous membranes of the respiratory, gastrointestinal tract and urinary tract.
4. Help Prevent Stroke and Heart Disease
Since antioxidants help prevent damage of tissues and cells caused by free radicals, they’re needed to protect against heart disease and stroke. At this point, the data does not show that all antioxidants are effective in protecting against heart disease, but some, such as vitamin C, do seem to be.
The American Journal of Clinical Nutrition featured a study that found those with high levels of vitamin C in their blood had almost a 50 percent decreased risk of stroke. Countless studies also have found that people who consume highly plant-based diets — loaded with things like fresh veggies, herbs, spices and fruit — have a better chance of living longer and healthier lives with less heart disease.
However, when it comes to heart health, certain studies have found that using vitamin E or beta-carotene supplements should be “actively discouraged” because of the increase in the risk of heart-related mortality, so consult a health professional when it comes to vitamin E or carotene supplementation.
5. May Help Reduce Risk of Cancer
Some research has unearthed a potential connection between antioxidants and cancer. In fact, studies have found that high intakes of vitamin A, vitamin C and other antioxidant foods could help prevent or treat several forms of cancer thanks to their ability to control malignant cells in the body and cause cell cycle arrest and apoptosis (destruction) of cancer cells.
Retinoic acid, derived from vitamin A, is one chemical that plays important roles in cell development and differentiation, as well as cancer treatment.
Lung, prostate, breast, ovarian, bladder, oral and skin cancers have been demonstrated to be suppressed by retinoic acid. Another study collected numerous references demonstrating the findings of retinoic acid in protection against melanoma, hepatoma, lung cancer, breast cancer and prostate cancer.
However, there’s evidence indicating that the benefits of chemicals like retinoic acid are safest when obtained from cancer-fighting foods naturally, rather than supplements.
6. Can Help Prevent Cognitive Decline
Oxidative stress is believed to play a central role in the pathogenesis of neurodegenerative diseases, but a nutrient-dense diet full of brain foods seems to lower one’s risk. The Journal of the American Medical Association of Neurology reports that higher intake of foods rich in antioxidants, such as vitamin C and vitamin E, may modestly reduce long-term risk of dementia and Alzheimer’s.
7. May Protect Against Diabetes
In addition to improving heart health and cognitive function, some research suggests that antioxidants could aid in the prevention of type 2 diabetes. For example, one animal model out of Japan showed that administering antioxidants to mice helped preserve the function of beta cells in the pancreas, which are responsible for the production of insulin.
Another large review of 12 studies found that vitamin E helped reduce blood sugar levels, while vitamin C was effective at decreasing levels of oxidative stress.
Antioxidants may be easier to add to your diet than you might think. Based on ORAC scores provided by Superfoodly (based on research from a broad number of sources), below are some of the top antioxidant foods by weight:
- Goji berries: 4,310 ORAC score
- Wild blueberries: 9,621 ORAC score
- Dark chocolate: 20,816 ORAC score
- Pecans: 17,940 ORAC score
- Artichokes (boiled): 9,416 ORAC score
- Elderberry: 14,697 ORAC score
- Kidney beans: 8,606 ORAC score
- Cranberries: 9,090 ORAC score
- Blackberries: 5,905 ORAC score
- Cilantro: 5,141 ORAC score
The ORAC scores above are based on weight. This means that it might not be practical to eat high amounts of all of these antioxidant foods.
Other high-antioxidant foods not listed above, which are still great sources and highly beneficial, include common foods like:
- pumpkin seeds
- sweet potatoes
- grapes or red wine
- wild-caught salmon
Try to consume at least three to four servings daily of these antioxidant-rich foods (even more is better) for optimal health.
Along with antioxidant foods, certain herbs, spices and essential oils derived from nutrient-dense plants are extremely high in healing antioxidant compounds. Here is another list of the herbs you can try adding to your diet for increased protection against disease.
Many of these herbs/spices are also available in concentrated essential oil form. Look for 100 percent pure (therapeutic grade) oils, which are highest in antioxidants:
- Clove: 314,446 ORAC score
- Cinnamon: 267,537 ORAC score
- Oregano: 159,277 ORAC score
- Turmeric: 102,700 ORAC score
- Cocoa: 80,933 ORAC score
- Cumin: 76,800 ORAC score
- Parsley (dried): 74,349 ORAC score
- Basil: 67,553 ORAC score
- Ginger: 28,811 ORAC score
- Thyme: 27,426 ORAC score
Other antioxidant-rich herbs include garlic, cayenne pepper and green tea. Aim to consume two to three servings of these herbs or herbal teas daily.
The American Heart Association, Mayo Clinic and Cleveland Clinic recommend getting antioxidants from whole foods and a wide variety of sources. While it’s always ideal, and usually more beneficial, to get antioxidants or other nutrients directly from real food sources, certain types may also be helpful when consumed in supplement form.
If you’re generally healthy and eat a varied diet, you might not benefit much from taking antioxidants supplements. However, if you’re at risk for something like vision loss or heart disease, talk to your health professional about whether the following antioxidant supplements in proper doses (and with a healthy lifestyle) might be helpful:
Glutathione is considered the body’s most important antioxidant because it’s found within the cells and helps boost activities of other antioxidants or vitamins. Glutathione is a peptide consisting of three key amino acids that plays several vital roles in the body, including helping with protein use, creation of enzymes, detoxification, digestion of fats and destruction of cancer cells.
Glutathione peroxidase can prevent lipid peroxidation, which can fight inflammation.
Derived naturally from foods like berries and leafy greens, quercetin seems to be safe for almost everyone and poses little risk. Most studies have found little to no side effects in people eating nutrient-dense diets high in quercetin or taking supplements by mouth short term.
Amounts up to 500 milligrams taken twice daily for 12 weeks appear to be very safe for helping manage a number of inflammatory health problems, including heart disease and blood vessel problems, allergies, infections, chronic fatigue and symptoms related to autoimmune disorders like arthritis.
Lutein has benefits for the eyes, skin, arteries, heart and immune system, although food sources of antioxidants seem to be generally more effective and safer than supplements. Some evidence shows that people who obtain more lutein from their diets experience lower rates of breast, colon, cervical and lung cancers.
4. Vitamin C
Known for improving immunity, vitamin C helps protect against colds, the flu, and potentially cancer, skin and eye problems.
Resveratrol is an active ingredient found in cocoa, red grapes and dark berries, such as lingonberries, blueberries, mulberries and bilberries. It’s a polyphonic bioflavonoid antioxidant that’s produced by these plants as a response to stress, injury and fungal infections, helping protect the heart, arteries and more.
Selenium is a trace mineral found naturally in the soil that also appears in certain foods, and there are even small amounts in water. Selenium benefits adrenal and thyroid health and helps protect cognition.
It may also fight off viruses, defend against heart disease and slow down symptoms correlated with other serious conditions, like asthma.
Chlorophyll is very helpful for detoxification and linked to natural cancer prevention, blocking carcinogenic effects within the body, and protecting DNA from damage caused by toxins or stress. It’s found in things like spirulina, leafy green veggies, certain powdered green juices and blue-green algae.
Preserving Antioxidant Levels
Cooking can alter the content of antioxidants in food, and certain cooking methods can have a different impact on antioxidant levels.
One study published in Preventive Nutrition and Food Science evaluated the effects of different cooking methods on the antioxidant content of red pepper to determine which methods can help minimize antioxidant loss. Interestingly, researchers found that stir-frying and roasting helped retain the most antioxidants, while boiling and steaming caused significant reductions in antioxidant levels.
Some antioxidant vitamins are especially prone to nutrient loss with cooking.
Ascorbic acid, also known as vitamin C, is a water-soluble vitamin, which means that it dissolves in water. For this reason, cooking food in water with methods like boiling can cause a huge reduction in antioxidant content.
However, not all compounds on the antioxidants list are affected in the same way by cooking. For example, one study found that consuming tomatoes cooked in olive oil significantly enhanced levels of lycopene in the blood by up to 82 percent compared to a control group.
Similarly, another study in British Journal of Nutrition showed that stir-frying carrots significantly boosted the absorption of beta-carotene.
Just like any other supplement, it doesn’t seem that it’s beneficial or even necessarily safe to consume high doses of antioxidants in supplement form. For example, because during exercise oxygen consumption can increase by a factor of more than 10, taking high doses of antioxidants might interfere with proper exercise recovery.
Other research has shown that high-dose antioxidant supplementation may interfere with the cardiovascular benefits of exercise, could have negative effects on the body’s natural anti-cancer activities and may affect how the body balances levels of different chemicals and nutrients on its own.
When it comes to protection against things like cancer or heart disease, overall the medical literature seems conflicting. Although some studies found a positive relationship between antioxidant supplementation and risk reduction, others have not found such positive effects.
To be safe, always follow directions carefully and speak with your health professional if you’re unsure of whether or not a supplement is right for you.
- What do antioxidants do, and how do antioxidants work? The official antioxidants definition is any substance that inhibits oxidation, which helps prevent free radical formation and protect against disease.
- The term refers to compounds that act as antioxidants, meaning that it includes a wide range of vitamins and minerals as well as other compounds like flavonoids, quercetin and rutin.
- Some of the top foods high in antioxidants include goji berries, wild blueberries, dark chocolate and pecans. However, they can also be found in a variety of other fruits, vegetables and herbs as well.
- What are the benefits of antioxidants, and what are antioxidants good for? Potential antioxidant benefits include improved vision, better brain health, a reduced risk of cancer, enhanced heart health and decreased signs of aging.
- Fortunately, there are plenty of simple ways to increase your antioxidants, which makes it easy to get enough of these important compounds in your daily diet.