Yeah multi vitamins are great, i stopped taking them and started getting loads of shitty little bugs. I eat healthy but just not enough fruit and veg(do now through RDJ smoothies idea!!) remember your body cant store vit c so it always good to keep topping up..
I recently started taking something called Echinacea which i have heard raving reviews about from people i know that take it,
Of the site i got it from...
Build up your defences against colds, flu and infections with this amazing supplement. Echinacea is well known for its powerful effect on the immune system, stimulating a group of cells that destroy bacteria and viral infections and speeding the healing of words.
Only just started taking it myself so can't comment yet but like i said heard good things...