Citrus such as oranges, mandarins, lemons, tangelos, tangerines have a lot of vitamin C, which can act as a natural antihistamine to help dry up some of that congestion and other allergic symptoms ...

Vitamin C halves their common cold risk, Johnston says. Vitamin C is also an antihistamine, so it can alleviate congestion, eye itching, runny nose and other cold and flu symptoms, she adds. For that ...