Pop quiz: What’s an antioxidant? If you’re not sure, you’re not alone. According to a recent survey by MonaVie, 92 percent of Americans don’t actually know what antioxidants are—even though 75 percent try to eat foods rich in the mysterious molecules.

Here’s the answer: Antioxidants are substances that protect your cells from free radicals, which are unstable molecules in the body that can cause DNA mutation. These are the three main types of antioxidants you encounter every day:

Carotenoids are common compounds found in produce that help reduce the damage from free radicals, fighting off certain types of cancers (including prostate, stomach, and colon) and slowing down vision loss in older adults. Carotenoids come in many forms that you might see on food labels, like beta-carotene, lycopene, and leutein.

Where to find them: In red, orange, and yellow vegetables like carrots and tomatoes; and dark green leafy vegetables like spinach and broccoli.

Vitamin E helps to protect your body from cell damage that can lead to cancers, heart disease, and vision degeneration.

Where to find it: In vegetable oils, whole-grain products, seeds, and nuts.

Vitamin C protects against infection and damage to cells. It also helps firm up your arteries and aids in the production of a compound called collogen, which keeps bones and muscles intact.

Where to find it: In citrus fruits like oranges, lemons, limes, and grapefruit; strawberries, sweet peppers, tomatoes, and broccoli.

For a complete breakdown—including which “antioxidant-rich” foods you may want to avoid—check out these 5 myths about antioxidants.

Source: Men’s Health