In my experience, a cold will last approximately a week no matter what you do. Any "remedies" simply alleviate the symptoms. The most effective ones are illegal for a medical professional to recommend, and stupid to take. One of those is hot rum and NeoCitran. My previous boss at the bar used that one. It didn't do a damned thing to cure the cold, but she didn't regain consciousness until it had died out on its own. Hot chicken soup is great, although I suspect that any hot soup would equal it, for two reasons: it provides nourishment to someone who might not be inclined to eat solid food, and it helps to clear the sinuses as any hot liquid will do.
Until I became permanently unemployed a year and a half ago, I missed 3 days due to illness in over 35 years of working.
The thing that I consider my favourite cold-weather food would probably work as a cold alleviation. In a large bowl, mix one can of Campbell's Chunky split-pea and ham soup, one can of Maple Leaf, Puritan, etc. ham, and a couple of tablespoons of cayenne powder. Mix well, nuke it for a minute or so, an eat it with whatever beverage you prefer.
That's the sort of thing that makes PF great.