Vitamin C and zinc haven't been shown to work as well as once thought, she said.
The herb echinacea has been shown to boost the immune system some. However, it shouldn't be taken for long periods of time, though, because it might overstimulate the immune system.
Franklin said besides getting your flu shot, two of the best ways to keep from getting or spreading the flu is to wash your hands frequently and cover your mouth with your inner elbow when you cough.
A more serious flu myth is that the flu shot can give you the flu. This isn't true, she said.
“One of the real things that can happen when people get a flu shot is that they can get a sore arm and they can get muscle aches, that's part of the body's response to the factors in the flu shot that are ramping up their immune system,” Franklin said.
“It's also true that it takes two weeks for the flu shot to kick in, and if you wait too long, especially during flu season, and you get exposed, it's only seven to 10 days from exposure before you get the symptoms.”