"Anti” means “against, or opposed to” and “oxidant” refers to the process of oxidation (when a molecular process in the body causes an increase in oxygen). So an antioxidant is a molecule that slows or stops an increase in oxygen. Now normally we think of oxygen as a great thing - we need it to live! But increasing oxygen in certain chemical reactions can cause free-radicals (molecules with unpaired electrons) due to the transfer of electrons that happens. A free-radical can be highly reactive due to that unpaired electron, which can cause damage to our cells and leave them susceptible to disease.
Antioxidants go in and fill in that missing electron, making the free-radical whole again. So you can imagine with pollution in the air, chemicals and pesticides in the water we drink and food we eat, sun damage to our skin, there is a lot of cell damage that happens to our bodies that leave plenty of free-radicals running around. So, in a nutshell, antioxidants are very important to our daily lives, which is why you're hearing the word so often.
There are many different types of antioxidants. They are split into 2 groups - those that are soluble in water and those that are soluble in lipids (fats). This matters in the body because we have both liquids (blood, etc) and lipids (cell membranes, etc) which are in need of antioxidant activity.
The Antioxidant in Red Wine
The antioxidant that is found in Red Wine, the alcohol most commonly associated with antioxidants is called "Resveratrol" which is considered a polyphenol antioxidant (the term refers to the chemical structure) and Phytonutrient (chemical compounds that naturally occur in plants). Studies of resveratrol in mice/rats have shown anti-inflammatory effects, blood sugar lowering effects, and may combat obesity, cancer and cardiovascular disease. However, most of these studies have not been repeated in humans yet.
Resveratrol is found in the skin of grapes used to make wine. The reason red wine is said to be higher in resveratrol than white wine is because red wine is fermented with the skins longer than white wine. But guess what? You can just eat grapes and skip the whole fermenting thing and still get the resveratrol - hellloooooo.....
Peanuts, blueberries and cranberries also have resveratrol. Below are a few charts for comparison.
Content in wines and grape juice
Beverage Total resveratrol (mg/150mL)
Rose Wines 0.06 - 0.53
Pinot Noir 0.06 - 0.30
White Wines 0.01 - 0.27
Content in selected foods
Food Serving Total resveratrol (mg)
Peanuts (boiled) 1 c 0.32 - 1.28
Peanut butter 1 c 0.04 - 0.13
Red grapes 1 c 0.24 - 1.25