To keep your lycopene straight from your flavonoids, we've put together an antioxidant lingo primer.

Bioavailability
The degree to which a nutrient or phytochemical can be absorbed by your body, determined by measuring how much enters your bloodstream. 

Your age, your health, and the way you prepare food all affect bioavailability. For example, cooking and fat make carotenoids more bioavailable, so you get even more lycopene from tomato sauce with olive oil than from a raw tomato. 

Free radical
An unstable molecule created in your body when you breathe, eat, or are exposed to pollutants such as cigarette smoke. Free radicals are unstable because of their missing electrons. To become stable, free radicals steal electrons from healthy cells in your body. 

ORAC value
"Oxygen radical absorbance capacity," or the number assigned to foods based on their performance in a test of antioxidant potential. The higher the number, the greater the supposed antioxidant power of the food. ORAC values are often based on dry weight, so dried fruits and spices score higher than water-filled foods such as fresh fruit. The USDA has compiled a list of more than 200 foods with their ORAC values; find it by visiting ars.usda.gov and typing "orac" in the search box. 

Oxidation
The loss of electrons that occurs when molecules come in contact with oxygen, which creates free radicals that cause cell damage (think of apple slices turning brown). Cell damage from oxidation can lead to a range of diseases, from atherosclerosis to cancer. 

Phytochemical
An umbrella term for any plant substance ("phyto" means plant) that's beneficial but not an essential nutrient (in the way vitamins and minerals are). Many, but not all, phytochemicals are antioxidants. 

Polyphenols
A group of antioxidant phytochemicals that includes flavonoids (antioxidant compounds that contain oxygen -- many common pigments are flavonoids) and phenols (acidic compounds).