What Are Antioxidants? Benefits, Side Effects And Best Sources

There are many antioxidants like Vitamin C, E and A, etc. Check out the benefits, side effects and best sources to consume them. Read on.

Navya Kharbanda
Written by: Navya KharbandaUpdated at: Feb 01, 2021 10:00 IST
 What Are Antioxidants? Benefits, Side Effects And Best Sources

Free radicals can be referred to as bad molecules that attack the essential molecules that promote necessary functions of the body. These are pro-oxidants which are produced due to either internal or external exposures. Anti-oxidants fight free radicals that are responsible for cardiac diseases, diabetes and cancer. Free radicals are naturally occurring in human metabolism, but an imbalance between free radicals and antioxidants can lead to some trouble. This imbalance is referred to as oxidative stress. Antioxidants are molecules that can prevent or slow down cellular damage done by free radicals, that are simply unstable molecules that are produced when the body reacts to environmental issues and other problems. Antioxidants are often called scavengers of free radicals.

The antioxidants produced by the body are known as endogenous antioxidants while those that come from outside the body are called exogenous antioxidants. Free radicals are produced by cells as waste product when the body processes food and reacts to the environment. If the body cannot process or remove free radicals efficiently, it can lead to an oxidative stress. This can be harmful to cells and overall function of the body. Free radicals are also called reactive oxygen species. The production of free radicals in the body can be caused due to internal factors like inflammation, or external factors such as cigarette smoke, pollution or UV exposure. Oxidative stress has been associated with cardiac diseases, stroke, cancers, immune deficiency, respiratory diseases, emphysema, parkinson’s disease, arthritis and other ischemic or inflammatory problems. Antioxidants are known to help balance out free radicals in our body, resulting in better overall health. Onlymyhealth editorial team spoke to Dr. Leena Saju, Division Head Dietetics, Artemis Hospitals, Gurgaon, about the benefits, side effects and best sources of antioxidants.

Types of antioxidants


There are hundreds and thousands of substances that can be called antioxidants. Each antioxidant has its own function to perform for the body, be it internally or externally. And, that is the reason why everyone should consume a balanced and nutritious diet, containing almost all the antioxidants. An antioxidant is not an actual substance but a word to explain about the various types of useful substances. Some antioxidants that are found in plant based foods or come from outside the body. According to Dr. Leena, some types of antioxidants are:

  • Vitamin A
  • Vitamin C
  • Vitamin E
  • Beta-carotene
  • Lycopene
  • Flavonoids
  • Flavones
  • Catechins
  • Polyphenols
  • Phytoestrogens
  • Phytonutrients
  • Lutein
  • Selenium
  • Manganese
  • Zeaxanthin
  • Copper

Benefits of antioxidants

heart health

The food items that are rich in antioxidants can help your body as well as skin. It protects you from damage and many chronic diseases too, by boosting your health. Many studies have proved that antioxidants even have cancer-protective properties present in them. As per Dr. Leena, here are the main benefits of antioxidants:

1. Good heart health

If you consume cucumbers in your daily diet, it can really help in the functioning of your heart. The antioxidants present in the fruit helps in curing or slowing down heart diseases. It can also keep your cholesterol balanced, leading onto good heart health. Antioxidants-rich vitamins such as vitamin C, beta-carotene and vitamin E help in maintaining good heart health.

Also read: 9 Foods That Have More Vitamin C and Antioxidants Than Orange

2. Enhances skin

Many foods have antioxidants like Vitamin E and Vitamin C that improve blood circulation, resulting in slowing down the skin aging process. Therefore, high antioxidant items can also make your skin look more soft, youthful and alive. And, you can get rid of various skin problems like pimples, eczema, etc.

3. Improves eyesight

High amounts of vitamin C are found in many fruits and vegetables, including bell peppers, citrus fruits, guavas, kale, and broccoli. Vitamin C is essential to maintain good eye health, and getting enough of this antioxidant may protect against cataracts. So, antioxidants are also good for your eyes and can improve weak eyesight.

4. Prevents cancer

Antioxidants guard against cellular damage caused by unstable molecules known as free radicals. Research and trials have indicated that antioxidants help in preventing damage that is caused by free radicals and associated with cancer. Selenium is a strong antioxidant that can help in protecting the heart and body from developing certain types of cancer. Vitamin C may also help in protecting against various diseases, including some specific kinds of cancers, and cardiac diseases.


5. Supplying Iron to tissues

This vitamin is a pro-oxidant (free radical damage causing) as well as an antioxidant. Copper is composed of a potent antioxidant enzyme and ceruloplasmin, the protein responsible for supplying iron to the tissues. 

6. Protects from cell damage and good for pregnant women

Vitamin C, which is one of the very important ingredients for a woman to intake during pregnancy is present in tomatoes abundantly. In fact, the lycopene antioxidant present in tomatoes helps in protecting you from cell damage. Including this item in your diet can help you and your baby to stay healthy.

Also read: 7 Health Wonders of Antioxidant-rich Foods

Side effects of antioxidants

One should never overconsume antioxidants be it through supplements or natural sources as it can damage your body in many ways. Taking high dosage of antioxidant supplements such as Vitamin A may even increase the risk of birth defects. If you are pregnant, always talk to your doctor before taking any supplements for antioxidants. It can also increase your risk of some types of cancers and can lower your exercise capabilities. According to Dr. Leena Saju, some common side effects of overconsuming antioxidants are diarrhea, dizziness and joint pain. You might also experience a yellow pigmentation of the skin due to the antioxidant carotene. Another rare side effect is bruising under the skin. Cooking some foods can either increase or decrease their antioxidant levels. They might also not react well for your body if consumed along with certain medicines. 

medicines and antioxidants

Foods high in antioxidants

Basically, antioxidants are molecules which you can scavenge to the pre radical thing in our body. Free radicals are basically like unstable molecules and its produced in our body due to air pollution or smoking toxic radiation. As per Dr. Leena, high antioxidant foods are:

1. Berries

All the berries including blueberries, strawberries blackberries, and raspberries are considered as highly nutritious fruits. They have the highest amount of antioxidants present in them. In fact, berries even help in reducing oxidative stress in the body. It is a low calorie food but loaded with nutrients.

2. Dark chocolate

It is also very rich in antioxidants as it contains high amounts of cocoa powder. So, you can have it in moderation without worrying about gaining weight. A study found out that dark chocolate may help in reducing the risk of heart diseases by raising blood antioxidant levels and avoiding the bad LDL cholesterol from getting oxidised.

Also read: Weight Management Tips: 4 Antioxidant-Rich Foods For Weight Loss

3. Tomatoes

Tomatoes contain lycopene, an antioxidant that benefits your health in many ways. They are also rich in natural vitamins and minerals like Vitamin A, K, B1, B3, B5, B6, B7, and vitamin C. Moreover, it also has folate, iron, potassium, magnesium, chromium, choline, zinc, and phosphorus. It can help in maintaining blood pressure and is good for pregnant women as well.

So, these were the benefits, side effects and best sources of antioxidants by Dr. Leena Saju and she recommends the consumption of a rainbow diet that includes all colours of foods. Antioxidants can be sourced naturally or artificially. Many plant-based foods are rich in antioxidants. Plant-based antioxidants are phytonutrients, or plant-based nutrients. Other high antioxidant foods except the above mentioned list are kale, beans, beetroot, spinach, oranges, grapes, nuts, sweet potato, etc.

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