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Antioxidants are naturally occurring compounds found in foods. Their primary role is to prevent the oxidation of other harmful compounds. Antioxidants prevent this oxidation by being oxidized themselves. The process of oxidation produces compounds called free radicals which, due to their composition, are very unstable. These free radicals may cause damage to the body, most commonly to the cell membranes. When the membranes are affected it alters the cells ability to function properly. Studies have suggested cancer, arthritis, cataracts, and heart disease may be the result of free radicals.

ORAC
Antioxidant activity in foods can be measured by units call ORAC (Oxygen Radical Absorbance Capacity). Canada’s Food Guide to Healthy Eating recommends 5-10 servings of vegetables and fruits daily, which is equivalent to 4000-7000 ORAC units/day. This unit of measure has been used on various apple products and shows that apple sauce contains 1635/125ml, apple juice contains 1700/250ml, Energy to Go bars by Sun Rype contain 3200/40g bar and Fruit to Go contain 1250/14g bar.

Antioxidants not only prevent the oxidation within the body but can also be used as preservatives to prevent the rancidity of fats and other damage, which occurs to food due to oxygen. Common antioxidants include Vitamin C, Vitamin E, Selenium, Carotenoids, Flavonoids and those of the Allium family.

Vitamin C can be found in many fruits and vegetables such as citrus fruits, apples, kiwi fruit, strawberries, broccoli, Brussels sprouts, bell peppers, potatoes and tomatoes. This vitamin is also present in fresh juices. To ensure you get the full benefits of this vitamin from the foods you eat, make sure you do not cook them at high temperatures for a long period of time, as it is heat sensitive. Also remember to use as little water as possible when cooking, as the vitamin is water soluble and can be lost easily. This vitamin is also commonly used as a preservative in food products and seen on food labels as ascorbic acid.

Vitamin E can be found in foods like vegetable oils, wheat germ, avocado, papaya, peanut butter, sunflower seeds and sweet potatoes. It is known to be one of the body’s primary defenders against free radicals. Its main action is to stop the chain reaction of free radicals from producing more free radicals. There is also a growing body of evidence that suggests that vitamin E may reduce the risk of heart disease, since it protects low density lipoproteins (LDL) from being oxidized. Vitamin E is also heat sensitive and is easily destroyed by cooking; therefore, it is wise to minimize heat exposure to maintain initial levels.

Selenium is a trace mineral that works with a specific enzyme, along with Vitamin E, to prevent free radical formation. It is usually found in protein foods such as seafood and meat but can also be found in whole grains and some vegetables (depending on the soil content that they were grown in). A deficiency of this antioxidant is associated with a predisposition to heart disease and possibly some cancers.

Flavanoids are powerful antioxidants and are found in a wide range of foods such as grains, vegetables, fruits, herbs, spices, teas, and red wine. They include categories such as quercetin, anthocyanidins, isoflavones, and catechins. Quercitin is found in apples, onions, and citrus fruits and plays a considerable role in preventing heart disease and cancer. Anthocyanidins are found in foods like bilberry, purple cabbage and grapes, and may play a protective role against the development of cataracts. Isoflavones, found in soy products, play a protective role against some cancers. Soy products can be consumed in many ways such as milks, cheeses and as the bean itself. Catechins are a powerful antioxidant, predominantly found in green teas. Avid drinkers have shown significantly lower risk of heart disease and cancers.

Carotenoids include beta carotene, lutein, and lycopene. These antioxidants are fat soluble and are mainly found in highly colored fruits and vegetables. Beta-carotene is largely found in dark green and orange-yellow vegetables such as spinach and carrots. Lutein is found in a wider variety of foods like kale, broccoli, leeks, peas and egg yolks. Lycopene is found primarily in tomatoes, pink grapefruit, guava and watermelon and has potent antioxidant capabilities. Carotenoids are sensitive to light, heat, and oxygen, thus minimal processing will help maintain the levels of these antioxidants. If you can’t eat the food sources in their fresh form, try steaming for shorter periods of time. The exception to this rule is tomato products, which contain much more lycopene than fresh tomatoes.

Allium antioxidants are found in foods like garlic, onions, chives and shallots. Garlic is known best for its role in helping to reduce the risk of cancer and heart disease. The main chemical found in garlic is called Alliin. When combined with the allinase enzyme, also found in garlic, a compound called Allicin is formed. This isolated, sulphur containing chemical is the compound that is responsible for the preventative effects. Try crushing garlic and onions into salad dressings and sauces for an extra antioxidant boost.

The bottom line Eat more antioxidant rich foods such as brightly coloured fruit and vegetables, whole grains, fish, nuts and seeds, to reduce your risk of cancer and heart disease.