I have a personal anctedote. That since I regularly drink 2-5 beers a day. Which I was never a regular(moderate but consistent) drinker daily since the last few years I notice if not by coicidence that my colds have only been short or never really full on bore into cold mode. Like,just a few sniffels or sneezes,but not anyfull blown colds like I use to have. I also exercise 2X more than I use to and have a good diet. But its amazing a cold has never developed more than just some sniffles and a few sneezes. I almost beleive its just the alcohol that kills the cold/flu stuff also. No conjestion,coughing.