Antioxidants are a class of nutrients that help protect the body from free radicals. These are unstable molecules that come from outside sources, like pollution, cigarette smoke, exposure to UV rays and X-rays, and from within the body as a byproduct of metabolism.
Antioxidants are identified as vitamins, minerals and phytochemicals found in plants. They are divided into two categories: water-soluble and fat-soluble. Fat-soluble antioxidants, like vitamins A, D, E and K dissolve in lipids or fats and protect cell membranes by preventing oxidation on a molecular level. Water-soluble antioxidants, like vitamin C and beta carotene dissolve in water and fight free radicals that attack our body's cells directly.
One of the most important functions of antioxidants is to reduce "inflammaging" within the body. Inflammaging is thought to be a factor in the development of chronic illnesses and age-related diseases. Researchers have found that increased inflammation is related not only to the aging process, but also to heart disease and many forms of cancer.
Nutrients like polyphenols, selenium, beta-carotene, lycopene and vitamins C and E have been shown in scientific studies to help protect the body from oxidative stress, improve immune function, strengthen cell membranes and support healthy aging.
The antioxidant content of many fruits and vegetables varies depending on the growing conditions, genetics and even the time of day. Science has discovered that consuming a variety of colorful fruits and vegetables everyday will ensure that you get the optimal levels of antioxidants for your body.
The following is a list of top antioxidant foods based on the ORAC (Oxygen Radical Absorbance Capacity) Scale:
Food: Serving size: ORAC value
Prunes or dried plums, 1/2 cup 2,343 units
Acai fruit pulp, 1/2 cup 2,050 units
Goji berry juice, 1/2 cup 2,000 units
Raisins or currants dry roasted with no added fat, 1/4 cup 676 units
Wild blueberries raw with skin on (small), 1/2 cup 650 units
Spinach cooked drained with no fat added (1/2 a 9 oz package of fresh spinach is used), 3 cups 563 units
Brewer's yeast (10 grams per day), 1 Tbsp 536 units* (see note)
Green tea brewed at.5 grams per cup 801 units
Black currents raw with skin on (small), 1/2 cup 565 units
Soybeans cooked with no added fat, 1/4 cup 486 units
Blackberries raw with skin on (small), 1/2 cup 451 units
Cranberries raw with skin on (small), 1/2 cup 446 units
Elderberries raw, 1/2 cup 405 units
Pomegranate arils or seeds raw, 1/3 cup 304 units
Dried plums or prunes (not packed in sugary juice or syrup), 6 pieces 189 to 257 units* (see note) *The FDA has not evaluated the ORAC values of these foods and may not have. Therefore, the values shown here may not be accurate. The values shown were determined by the University of Illinois at Chicago and are cited in "ORAC Values of Selected Foods", Journal of Agricultural and Food Chemistry, volume 58, pages 4656–4662, October 2010.
It is important to remember that these antioxidant levels are not definitive with all foods. The extra sugar added during processing increases the amount of sugars in a food and raises the ORAC level. In some cases a high ORAC level can mask a nutrient deficiency because antioxidants work best when combined with other nutrients. Therefore it is important to consult a reputable nutritionist to find out whether you are getting optimum antioxidant support from your diet.
Providing antioxidants via supplements is also helpful for many people. Some of the most popular antioxidant supplements include:
Vitamin C Vitamin C (ascorbic acid) is one of the most well known and widely used antioxidant vitamins in the world. As a water-soluble antioxidant, vitamin C helps to reduce the damage caused by free radicals. It also has been shown to stimulate collagen production, support healthy immune function, stimulate detoxification and help with wound healing. Non-citrus fruits like guava, mangoes, kiwi and broccoli are good dietary sources of vitamin C. This vitamin can be found in supplemental form in tablets or powder form that is mixed into food or drinks like water or fruit juice. Some people have difficulty absorbing vitamin C in its pure form, however it is also found naturally in several fruits and vegetables and may be added to foods as a food additive. Vitamin C deficiency may decrease immune function and contribute to the development of some diseases, including some forms of cancer. Some people with kidney disease or liver disorders, low iron levels or poor absorption may not be able to absorb vitamin C. Therefore it is important for people to consult their doctor prior to taking vitamin C supplements.
Vitamin E Vitamin E (tocopherol) is one of the most well-known antioxidants in the world. This fat-soluble nutrient is similar to vitamin C and also helps to protect the body from damage caused by free radicals. It is found in foods including almonds, avocado, apricots, blackcurrants, olives, nuts and sunflower seeds. Vitamin E also provides support for tissue repair. Some people may be sensitive to vitamin E and because of their condition may not be able to consume this supplement. If a person with a rare genetic disorder that affects vitamin E absorption cannot take large amounts of this vitamin it can lead to severely damaged red blood cells. Therefore it is important that people with these conditions consult their doctor before taking supplements containing vitamin E.
Ascorbic acid (Vitamin C) Tablets Ascorbic acid or Vitamin C (ascorbic acid) is an essential water-soluble antioxidant. This vitamin is essential for the maintenance of good health. As this nutrient plays a role in collagen production, it has also been shown to help with wound healing and support healthy immune function.
Antioxidants work best when taken in conjunction with other nutrients. Therefore, it is important to consult your doctor before starting a supplement regimen, especially if you are taking medications that may be contraindicated or if you have any other health conditions or questions about your supplement needs.
Dr. Dawn Helin is a licensed naturopathic doctor with a private practice in Portland, Maine. She is the author of The Best Oils for Cooking: Recipes and Essential Guide to Using the Healthiest Oils in Your Kitchen (March 2013) and Healthy Meals to Go: Over 50 Fast, Easy, Delicious Recipes for Eating Well at Home or on the Go (January 2012). Dr. Helin graduated from NCNM (National College of Naturopathic Medicine) in 2003 and has been involved with wellness education and community health for over 10 years. She is originally from Lexington, Massachusetts but has lived on the East Coast and in Oregon before making her home in Maine with her husband and three children. Dr. Helin is a regular contributor to the online health magazine, The Doctors Book of Home Remedies. She can be contacted at drdawnhelin@gmail.com .
