Antioxidants are nutrients in our foods that can slow and prevent the occurrence of free radicals within the human body.
We've all herd antioxidants are good for you, yet do we really know what they are or where to find them?
Research studies are looking into how plant-based antioxidants and herbal supplements can be useful in the promotion of health and prevention of chronic diseases.
Vitamin C, E, A, selenium, zinc and a group known as the carotenoids (pigments that add color to many fruits and vegetables) serve as antioxidants. These substances are thought to be effective in helping to prevent cancer, heart disease, stroke, and various other ailments
Are we getting enough of them? How do they actually work?
Researcher Dr. Susanne Mertens- Talcott of Texas A&M University (a joint researcher with the department of nutrition, food science, and department of veterinary physiology and pharmacology) says money spent on antioxidants and herbal supplements among U.S. citizens was more than million in 2005.
"Over billion was spent on herbal dietary supplements in 2005." These supplements are plant-based, including grape seed extract, St. John's wort, ginseng and biloba extract, she added. "In addition to that there is the segment of so-called ‘functional foods,' including antioxidant foods - for example, fruit juices and beverages and grain-based products," Talcott said.
The amount spent on these foods each year "has increased drastically; however, we do not know yet how efficacious these different antioxidants really are in the prevention of chronic diseases such as cardiovascular disease and cancer," she said. "We also do not know very much about the mechanisms, which appear to include antioxidant and anti-inflammatory effects of these phytochemicals."
This can be important to health since these reactive oxygen species, or free radicals may play a role in some diseases including alzheimer's, cancer and atherosclerosis, she said.
Free radicals are airborne molecules that are natural by-products of various environmental factors. These molecules want to be chemically processed. Our bodies breath in these free radicals and so the process begins- referred to as oxidization - the same process as if you smoked a cigarette. However, sometimes this oxidization can cause cancer inducing properties that alter alter cellular metabolism, or damage DNA directly in cells - interfering with our normal biological process.
"My overall goal is to find out more about the safety and efficacy of phytochemical dietary supplements," Talcot said. Because these items are already popular with consumers, "we need to follow up with research. We know very little about (dose) recommendations and how safe (they are)."
Pomegranate juice and extract have been the focus of much of her studies. Because these are used in different food products, they are found as ingredients in many different items in supermarkets, Talcott said.
Talcotts research also analyzes properties of muscadine grapes and acai, a palm fruit from Brazil, as well as isolated compounds including quercetin and ellagic acid, which are also sold as dietary supplements.
"It is my long-term goal to see science-based intake recommendations developed for those herbal plant compounds which have a proven potential in the promotion of health and prevention of chronic disease." Talcott said.
Antioxidants are found in beans, grain products, fruits and vegetables. Look for fruits with bright color - lutein in some of the yellow pigments found in corn; orange in cantaloupe, butternut squash and mango; red from lycopene in tomatoes and watermelon, and purple and blue in berries. It is best to obtain these antioxidants from foods instead of supplements. In addition, minimize the exposure of oxidative stress such as smoking and sunburn.
Common Forms Of Antioxidants
Vitamin A, and Carotenoids
Carrots, squash, broccoli, sweet potatoes, tomatoes, kale, collards, cantaloupe, peaches and apricots (bright-colored fruits and vegetables!)
Vitamin C
Citrus fruits like oranges and lime etc, green peppers, broccoli, green leafy vegetables, strawberries and tomatoes
Vitamin E
Nuts & seeds, whole grains, green leafy vegetables, vegetable oil and liver oil
Selenium
Fish & shellfish, red meat, grains, eggs, chicken and garlic