Pears are a natural immune system booster. Pears contain antioxidants such as vitamin C and copper and are considered to be a hypoallergenic food.
Squeeze a lemon wedge into your iced or hot tea. The acidity can boost antioxidant concentrations in green tea by 20 percent, according to a study in the journal Food Chemistry. Researchers believe the same trick works with all kinds of tea.
Tired of orange juice? Try mixing it up with grape juice, it has twice the natural antioxidants.
Dark chocolate packs flavonoids that act as antioxidants, protecting cells from damage.