Fight Free Radicals

May 06, 2011

We have all heard of antioxidants, but where do they come from and why do we need them?

We have all heard of antioxidants by now and are aware that they have the potential to improve overall health, delay the onset of many age-related diseases, prevent macular eye disease and reduce the risk of some cancers, and more. SupermarketGuru has been seeing a lot more products on the shelves using antioxidant content as a selling point. Often the ORAC value is cited and we wanted to refresh you on some of the basic definitions and what to look out for on food labels when shopping and choosing foods.

What are Antioxidants? Antioxidants are nothing more than vitamins, A, C and E, the mineral selenium, and bioactive compounds like carotenoids and polyphenols found in foods. Our need for them is derived from a paradox in metabolism. Our bodies require oxygen to function, but oxygen - by itself - is highly reactive, and creates harmful byproducts through oxidation. These byproducts, called free radicals, are potentially damaging to cells. Antioxidants, as the name reveals, can stabilize free radicals before they cause harm.

Our body’s defense against oxidative stress decreases over time, which is why a diet rich in antioxidant foods is needed as we age. Oxidation is a normal process that occurs in the body through normal cell function and metabolism - as well as from outside sources which include pollution, radiation, cigarette smoke, motor vehicle emissions, and many other processes. Environmental free radicals then enter the body through the skin, respiration, and other means. Therefore, achieving a balance with an antioxidant rich diet is crucial to maintaining good health.

A food's antioxidant power is measured in units called ORACs, or Oxygen Radical Absorbance Capacity, referring to how much radical oxygen a food can absorb. The ORAC scale was developed by USDA researchers at Tufts University in order to inform the public about different foods' antioxidant capacity.

Which foods contain the highest ORAC value? One hundred grams of grapes (about 23 grapes) rates 739 on the ORAC scale; 100 grams (about 70 blueberries) of blueberries rakes in at 2,400, raspberries (about 50) 1,220. One hundred grams of kale and spinach (about a cup and a half) contain 1,770 and 1,260 respectively. And chocolate? 100 grams contains a whopping 13,120 ORAC! (but be careful because that is unsweetened cacao and not a milk and sugary sweetened chocolate bar).

Individual colors are important indicators - darker foods, like pomegranates (3,037 ORAC) and plums (949), tend to be more antioxidant-rich. Orange foods like sweet potatoes, carrots, and pumpkin contain beta-carotene. Lutein, known for its association with healthy eyes, is abundant in greens.

Supermarket Guru suggests sticking with the natural foods mentioned above as well as nuts, and grains. Some other vitamin A rich foods include liver, milk, and egg yolks; vitamin E is found in broccoli, almonds, and mangos, while whole grains provide selenium. Because it may be harder to absorb antioxidants from antioxidant-enhanced food products it's best to stick with natural sources and the foods mentioned above, but if you feel you need a quick fix, look for products that clearly state the ORAC value of what’s inside- and do be mindful of sugar content and other nutrition don’ts.