I got a cold this winter. Found all my cold remedies had expired back in 2001. So I think it'd been about 4 years between colds for me! For me, I think my paying attention to where my hands have been, frequent hand-washing, trying not to touch things like door knows in restrooms (I pull my sleeves over my fingers, like a glove) and just not being around children much, has a lot to do with my lack of colds.