Quoted from Wickerman2:I cut way back a few years ago—essentially zero—-and I think I catch less in the way of colds etc. Not sure if I have any science to back that up but seems that way.
It's plausible. Viruses and bacteria love carbs...including alcohol sugars.
It's anecdotal, but I went on the Keto diet and a couple months ago everyone I work with caught the flu passing it around to each other - except for me. I'm going back on the diet.