Indeed, too much of these antioxidant supplements won't help you and may even harm you. It is better to supply your antioxidants from a well-rounded diet. To learn more about the vitamins and minerals you need to stay healthy, read Making Sense of Vitamins and Minerals , a Special Health Report from Harvard Medical School.

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Shining light on night blindness. Can watching sports be bad for your health? Beyond the usual suspects for healthy resolutions. January 31, Some vitamins and minerals — including vitamins C and E and the minerals copper, zinc, and selenium — serve as antioxidants, in addition to other vital roles.

Share This Page Share this page to Facebook Share this page to Twitter Share this page via Email. Print This Page Click to Print. Related Content. Staying Healthy. Heart Health. Free Healthbeat Signup Get the latest in health news delivered to your inbox! For instance, vitamin C is often added to processed foods to act as a preservative Your diet is an essential source of antioxidants, which are found in animal and plant foods — especially vegetables, fruits, and berries.

Water-soluble antioxidants perform their actions in the fluid inside and outside cells, whereas fat-soluble ones act primarily in cell membranes. Notable examples include curcuminoids in turmeric and oleocanthal in extra virgin olive oil.

These substances function as antioxidants but also have potent anti-inflammatory activity 19 , Some studies even show that high doses of antioxidants increase your risk of death 23 , For this reason, most health professionals advise people to avoid high-dose antioxidant supplements , although further studies are needed before solid conclusions can be reached.

Eating plenty of antioxidant-rich whole food is a much better idea. Studies indicate that foods reduce oxidative damage to a greater extent than supplements.

For example, one study compared the effects of drinking blood-orange juice and sugar water, both of which contained equal amounts of vitamin C. It found that the juice had significantly greater antioxidant power The best strategy to ensure adequate antioxidant intake is to follow a diet rich in various vegetables and fruits, alongside other healthy habits However, low-dose supplements, such as multivitamins, may be beneficial if you are deficient in certain nutrients or unable to follow a healthy diet.

Studies suggest that taking regular, high-dose antioxidant supplements may be harmful. If possible, get your daily dose of antioxidants from whole foods, such as fruits and vegetables. Adequate antioxidant intake is essential to a healthy diet, although some studies suggest that high-dose supplements may be harmful.

The best strategy is to get your daily dose of antioxidants from healthy plant foods, such as fruits and vegetables. Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available. Coffee is incredibly high in antioxidants.

Several studies have shown that people get more antioxidants from coffee than any other food group. Antioxidant supplements are popular, but evidence suggests that they have several drawbacks. This article explains what antioxidant supplements are….

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A Quiz for Teens Are You a Workaholic? How Well Do You Sleep? Health Conditions Discover Plan Connect. Nutrition Evidence Based Antioxidants Explained in Simple Terms. By Atli Arnarson BSc, PhD on July 12, What they are Free radicals Food sources Antioxidant types Supplements Bottom line Antioxidants are molecules that can help your body fight off harmful free radicals, which have been linked to health conditions like diabetes and cancer.

What are antioxidants?

This nutrient is naturally occurring in many plant-based foods, and it not only acts as an antioxidant, but it revives other antioxidants attacked by free radicals such as vitamin E. Research suggests vitamin C may help protect against various diseases , including certain types of cancers, and heart disease.

Foods high in vitamin C include: 7. This vitamin exists in two forms: inorganic selenate and selenite and organic selenomethionine and selenocysteine. Selenium is a powerful antioxidant that may help protect the heart and body from developing certain types of cancer.

Foods high in selenium include: This vitamin is both a pro-oxidant meaning it causes free radical damage and an antioxidant.

Not getting enough copper affects the levels of selenium, iron, catalase, and glutathione — all powerful antioxidants. Foods high in copper include: Like copper, manganese is a powerful antioxidant. Manganese superoxide dismutase MnSOD is the main antioxidant enzyme in the mitochondria of every cell in the body.

Foods high in manganese include :. This vitamin is instrumental in the activity of about enzymes in the body. Foods high in zinc include:. This nutrient helps protect the cell membrane from damage oxidation. Nonheme iron is found in plant foods and fortified foods, while meat, seafood, and poultry contain both nonheme and heme iron.

Foods high in iron include: Enzymes convert free radicals to hydrogen peroxide and then water using a process that includes copper, zinc, manganese, and iron. Superoxide Dismutases SODs These are the major antioxidant defense system against free radicals.

Formed in the body, they do require copper and manganese to make them work. There are three forms: two varieties of copper-zinc superoxide dismutase CuZnSOD with one being in the cell and one located outside the cell, as well as manganese superoxide dismutase MnSOD.

Glutathione Peroxidase GSHPx This is a cell antioxidant enzyme that reduces hydrogen peroxide to water.

Catalase CAT This is also responsible for changing hydrogen peroxide to water using iron as its assistant called a cofactor. The upshot is how important it is to eat foods rich in these minerals. Any deficiencies could mean a reduction in antioxidant activity that can increase the oxidative stress you may be under.

Herbs and spices contain compounds that have antioxidant effects on the body. In particular, research has zeroed in on the contents of phytonutrients flavonoids. These natural oils contain antioxidant and anti-inflammatory properties.

Several factors can influence their effects — including harvesting time, mode of intake skin, ingestion, or inhalation , temperature and weather, and growth and oil extraction methods. Food and Drug Administration FDA for a list that is generally recognized as safe. Supplementing your diet is another way you can up your antioxidant intake.

Supplements often come with a variety of the necessary forms of vitamins E and C and selenium. But with antioxidant supplements, balance is key.

Some studies suggest that certain antioxidants, such as beta-carotene and vitamin E, may increase mortality, with a possible similar outcome with vitamin C and selenium but more studies are needed. For people with cancer , antioxidant supplements may be counterproductive, causing cancer cells to grow rather than die in some cases.

Additionally, supplements may interact with cancer treatment or medications and should be avoided. And remember, supplements fall under the Dietary Supplement Health Education Act DSHEA , but are not regulated for safety or efficacy by the FDA. Antioxidants are powerful components that may help protect your body from disease.

When possible, enjoy foods rich in a variety of antioxidants to reap all their possible health benefits. If you choose to supplement or use essential oils to get your fix, consult your healthcare team to see if this is the right fit for you. Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy.

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What Is an Antioxidant, and Why Is It Important? Next up video playing in 10 seconds. Phytonutrients These are chemical compounds found in plants, and they have a variety of possible health benefits for the body, including antioxidant activity.

Foods high in vitamin E, along with their daily values DVs , include: 5 Wheat germ oil 1 tablespoon [tbsp] , percent DV Sunflower seeds, dry roasted 1 ounce [oz] , 37 percent DV Almonds , dry roasted 1 oz , 34 percent DV Sunflower or safflower oil 1 tbsp , 25—28 percent DV Hazelnuts, dry roasted 1 oz , 22 percent DV Vitamin C If you see ascorbic acid listed on your food labels, your eats contain vitamin C.

Copper This vitamin is both a pro-oxidant meaning it causes free radical damage and an antioxidant. Editorial Sources and Fact-Checking. Resources Phaniendra A, Jestadi DB, Periyasamy L.

Free Radicals: Properties, Sources, Targets, and Their Implication in Various Diseases. Indian Journal of Clinical Biochemistry. January Betteridge DJ. What Is Oxidative Stress? Metabolism: Clinical and Experimental.

February 1, What Are Phytonutrients? Produce for Better Health Foundation. Jeeva JS, Sunitha J, Ananthalakshmi R, et al. Enzymatic Antioxidants and Its Role in Oral Diseases. August Vitamin E: Fact Sheet for Health Professionals. National Institutes of Health. March 26, Jacob R, Sotoudeh G.

Vitamin C Function and Status in Chronic Disease. Nutrition in Clinical Care. March—April Vitamin C: Fact Sheet for Health Professionals. Harvard T. Chan School of Public Health. Erdman JW, Macdonald IA, Zeisel SH. They do not recommend that people take high-dose antioxidants supplements unless specifically recommended by a healthcare provider.

There is no doubt that consuming a diet high in antioxidant-rich foods is beneficial for health and may help prevent disease development. It is best to avoid high-dose antioxidant supplements unless a trusted healthcare provider prescribes or recommends them.

The best way to take in antioxidants is through foods and beverages, such as vegetables, fruits, nuts, fish, spices, and tea.

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Aune D, et al. Dietary intake and blood concentrations of antioxidants and the risk of cardiovascular disease, total cancer, and all-cause mortality: A systematic review and dose-response meta-analysis of prospective studies. American Journal of Clinical Nutrition.

Carlsen MH, et al. The total antioxidant content of more than foods, beverages, spices, herbs and supplements used worldwide. Nutrition Journal.

Zeratsky KA expert opinion. Mayo Clinic. Izquierdo-Vega JA, et al. Evidence of some natural products with antigenotoxic effects. Part 1: Fruits and polysaccharides.

Lopez-Romero D, et al. Part 2: Plants, vegetables, and natural resin. Rusu ME, et al. Health benefits of nut consumption in middle-aged and elderly population. Antioxidants Basel.

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International Patients. Financial Services. Community Health Needs Assessment. The sources of antioxidants can be natural or artificial. Certain plant-based foods are thought to be rich in antioxidants. Plant-based antioxidants are a kind of phytonutrient, or plant-based nutrient.

The body also produces some antioxidants, known as endogenous antioxidants. Antioxidants that come from outside the body are called exogenous. Free radicals are waste substances produced by cells as the body processes food and reacts to the environment.

If the body cannot process and remove free radicals efficiently, oxidative stress can result. This can harm cells and body function. Free radicals are also known as reactive oxygen species ROS.

Factors that increase the production of free radicals in the body can be internal, such as inflammation , or external, for example, pollution, UV exposure, and cigarette smoke.

Antioxidants are said to help neutralize free radicals in our bodies, and this is thought to boost overall health.

Antioxidants can protect against the cell damage that free radicals cause, known as oxidative stress. Activities and processes that can lead to oxidative stress include :. The damage caused by oxidative stress has been linked to cancer, atherosclerosis , and vision loss.

It is thought that the free radicals cause changes in the cells that lead to these and possibly other conditions. Other research has indicated that antioxidant supplements may help reduce vision loss due to age-related macular degeneration in older people.

Overall, however, there is a lack of evidence that a higher intake of specific antioxidants can reduce the risk of disease. In most cases, results have tended to show no benefit, or a detrimental effect, or they have been conflicting.

There are thought to be hundreds and possibly thousands of substances that can act as antioxidants. Each has its own role and can interact with others to help the body work effectively. Flavonoids, flavones, catechins, polyphenols, and phytoestrogens are all types of antioxidants and phytonutrients, and they are all found in plant-based foods.

Each antioxidant serves a different function and is not interchangeable with another. This is why it is important to have a varied diet. To obtain some specific antioxidants, try to include the following in your diet:. Vitamin C : Most fruits and vegetables, especially berries, oranges, and bell peppers.

Vitamin E : Nuts and seeds, sunflower and other vegetable oils, and green, leafy vegetables. Beta-carotene : Brightly colored fruits and vegetables, such as carrots, peas, spinach, and mangoes. Lutein : Green, leafy vegetables, corn, papaya , and oranges. Selenium : Rice, corn, wheat, and other whole grains, as well as nuts, eggs, cheese, and legumes.

Goji berries and many other food products that contain antioxidants are available to purchase online. The following foods are good sources of antioxidants. Click on each one to find out more about their health benefits and nutritional information:.

Lycopene is the antioxidant that gives tomatoes their rich red color. When tomatoes are heat-treated, the lycopene becomes more bio-available easier for our bodies to process and use.

However, studies have shown that cauliflower, peas, and zucchini lose much of their antioxidant activity in the cooking process. Keep in mind that the important thing is eating a variety of antioxidant-rich foods, cooked and raw. There is no set recommended daily allowance RDA for antioxidants, but a high intake of fresh plant-based produce is considered healthful.

It is worth remembering that, while studies link the consumption of fruits and vegetables with better overall health, it is not clear whether how far this is due to the activity of antioxidants.

In addition, caution is needed regarding supplements. The National Institutes of Health NIH warn that high doses of antioxidant supplements can be harmful.

A high intake of beta-carotene, for example, has been linked to an increased risk of lung cancer in smokers. A high dose of vitamin E has been found to increase the risk of prostate cancer , and the use of some antioxidant supplements has been linked to a greater risk of tumor growth.

Antioxidant supplements may also interact with some medications. It is important to speak with a health provider before using any of these products. Overall, research has not proven that taking any particular antioxidant as a supplement or through a food can protect against a disease.

There may be some benefit for people at risk of age-related macular degeneration, but it is essential to seek advice from a doctor about whether to use supplements, and which ones to use.

Free radicals have been linked to a range of diseases, including heart disease, cancer, and vision loss, but this does not mean that an increased intake of antioxidants will prevent these diseases.

Antioxidants from artificial sources may increase the risk of some health problems. As a result, it is important to seek out natural sources of antioxidants, in the form of a healthful diet. Consuming fruits and vegetables has been linked to a lower rate of chronic diseases, and antioxidants may play a role.

However, it is unlikely that consuming added antioxidants, especially in processed foods, will provide significant benefits. In addition, anyone considering taking antioxidant supplements should speak to a health provider first.

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