Below general information is a table listing various compounds reported to be antioxidants.

General Information: In order to understand how important antioxidants are it is important to understand what oxidation and oxidative stress is. In simplicity oxidants are unbalanced electrons 1,3,5 etc. that attach to our cells and cause corrosion similar to rust on steel. Antioxidants are balanced electrons such as 2, 4, 6 etc. Human oxidation is similar to oxidized paint on our automobiles when they fade and loose their luster. Or like the corrosion that occurs in car battery cables allowing the acids to eat away the cable and corrode the battery post to stop electrical flow. Oxidants do the same to our cells. Oxidation causes health problems such as dementia, aging, lung problems and many more. Anti oxidants are items that remove oxidants and are in the chemistry world called reducers or redux hence antioxidants are not just important but are life saving.

You cannot expect antioxidants to over power
oxidants, you must FIRST STOP ingesting oxidants!!!

Some claim a ratio of 70% antioxidants to 20%
oxidants is required for proper health.
Some oxidants are essential for us such as oxygen

If we keep eating oxidant foods, drinking alcohol, carbonated drinks or smoking we cannot expect antioxidants to do much for us!!!

The process of spoiling foods is a chemical transition of oxidants replacing antioxidants.This means hamburger or fruit in its purest form can be full of antioxidants but as it spoils it becomes full to toxic oxidants. Green and Black teas come from the same leaf. The green tea is full of antioxidants. Black tea is prepared by making rows of the green leaf exposed to the elements and turning it as it blackens and chemically replacing antioxidants with poisonous toxins and fungus. Many foods will change from antioxidant state to oxidative state in the spoiling process. Thus eating oxidant foods or drinks is like eating spoiled meat. Antioxidants help remove oxidants but cannot be expected to overcome them if we keep adding them to our body. When we stop ingesting oxidants then antioxidants can begin to clean up our body. Carbonated drinks especially those with caffeine and the new sports drinks are destroying health because they are full of poisonous oxidants. It is a terrible situation that the things that are advertised and popular such as tobacco, alcohol, black tea, coffee, and soft drinks are destroying our health, and few recognize it. Add to this the harm caused by many food oxidative additives and we hardly have a chance to maintain our health. Since WWII the incidence of disease has increased at an alarming rate. This increase correlates to the increase of pesticides, chemicals, and food additives.

Next are some research reports about oxidants vs. antioxidants. After the reports is a table listing some antioxidants.

1. Medicine Plus: "Antioxidants are substances that may protect your cells against the effects of free radicals. Free radicals are molecules produced when your body breaks down food, or by environmental exposures like tobacco smoke and radiation. Free radicals can damage cells, and may play a role in heart disease, cancer and other diseases. Antioxidant substances include: Beta-carotene, Lutein, Lycopene, Selenium, Vitamin A, Vitamin C, Vitamin E.  Antioxidants are found in many foods. These include fruits and vegetables, nuts, grains, and some meats, poultry and fish." http://www.nlm.nih.gov/medlineplus/antioxidants.html

2. American Heart Association: "What are antioxidant vitamins? Much research has recently focused on how antioxidant vitamins may reduce cardiovascular disease risk. Antioxidant vitamins — E, C and beta carotene (a form of vitamin A) — have potential health-promoting properties. Though the data are incomplete, up to 30 percent of Americans are taking some form of antioxidant supplement...The American Heart Association doesn't recommend using antioxidant vitamin supplements until more complete data are available. We continue to recommend that people eat a variety of nutrient-rich foods daily from all the basic food groups. Eating a variety of foods low in saturated fat, trans fat and cholesterol will provide a natural source of these vitamins, minerals and fiber." http://www.americanheart.org/presenter.jhtml?identifier=4452

3. Pub Med: Nutr Metab (Lond). 2007; 4: 8. "Thus, the beneficial effects of curcumin on the metabolic abnormalities postulated to be important in the development of diabetic retinopathy suggest that curcumin could have potential benefits in inhibiting the development of retinopathy in diabetic patients." (3) Curcumin as an antioxidant may prevent blindness in diabetics.

4. USDA Food Rich in Antioxidants Offer Important Protection By Gerald F. Combs, Jr."Not many people think of oxygen as being toxic, but it's true. Of course, we need oxygen to stay alive--that's why we breathe. And we need more of it when we are doing physical work or strenuous exercise. That's why we breathe harder and faster--to get more oxygen to enable our cells to produce more energy. But it turns out that some of the oxygen that we inhale is--through our own metabolism--turned into highly reactive forms that can interfere with essential functions within cells. "Research has shown that these reactive forms of oxygen are also necessary for certain essential functions. We use reactive oxygen to kill bacteria and to signal functional changes within blood vessels. But when produced in excess, reactive oxygen can also damage proteins, fats and DNA inside of cells. In this way, adverse effects of oxygen have been linked with cardiovascular disease and cancer, and also with aging, arthritis, cataracts, diabetes and impaired immune function. Because these reactions involve oxygen, they are called "oxidations". On the other hand, there are also ways to protect cells against such oxidative damage by blocking these oxidation reactions. Factors that do this are called "anti-oxidants". Because blocking oxidative damage may lead to reduced risks of chronic disease, there is enormous interest in the health roles of antioxidants." http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1868028

4. A recent query on the USDA web site showed 4,530 reports about antioxidants. Many web sites are quoting a USDA report showing 20 top antioxidant foods see study 1 below.  I could not find a reference to the report on any of the sites I visited so I searched the FDA site and could not find the article. I did find two other articles that have similar study's and observed that each of the three studies are different. The numbers for each do not correlate because the quantity of food for each study is different thus will effect the numbers. I put them here for comparison and information with the sources that I found for each. Although there is some controversy as to what foods are the best, it shows foods that have high levels of antioxidants. http://www.ars.usda.gov/News/docs.htm?docid=15074

(1) http://seniorjournal.com/NEWS/Nutrition-Vitamins/4-06-23Antioxidants.htm

(2) http://www.webmd.com/food-recipes/news/20040617/antioxidants-found-unexpected-foods

(3) http://www.ars.usda.gov/is/np/fnrb/fnrb499.htm#Contents

Other info http://www.ars.usda.gov/is/pr/2007/071106.ht