There's a long-running debate in my family about one particular expression - one which might be relevant to anyone who, like me, has a blocked up nose at the moment. It's Winter. It comes with the territory.
Anyway, the contentious phrase is this: "Feed a cold, starve a fever."
Pretty well known, pretty widely used by parents and grandparents throughout Britain, at least. And what does everybody think it means? Presumably this: "If you have a cold, eat lots. If you have a fever, don't eat very much at all. That's the way to get better."
OK, fine. The thing is though - THAT'S CLEARLY RIDICULOUS.
Ahem. Let me get my ranting boots on.
In the past I've read a couple of supposed 'medical' justifications of this interpretation, claiming the proverb originates from 16th century medical practice. These explanations are at best very tenuous, at worst very wrong. It's all a misinterpretation of the phrase, which I will now attempt to correct in two stages.
1 - It's not an instruction. Compare the phrase "Act in haste, repent at leisure." It doesn't mean I'm telling you that you ought to act in haste, does it? What it's saying is that IF YOU act in haste THEN YOU WILL HAVE TO repent at leisure. There are many phrases which use the same structure (I've listed a few further down if you need convincing). "Feed a cold..." is another example. They are all "If... then..." sentences:
IF YOU feed a cold THEN YOU WILL HAVE TO starve a fever. It's not an instruction, it's a warning.
Which leads me to my next point.
2 - It's nothing to do with food. It's a metaphor. And it astounds me that people don't realise this. Isn't it obvious? If you 'feed' a cold (by doing things likely to aggravate it, like going out with wet hair on a chilly day) then your cold will develop into a fever, which you will then have to 'starve' (by doing everything you can to fight the illness and stop it getting worse).
Why does it annoy me so much when I hear the phrase mis-used?
Here are some other proverbs with simliar structures. Read them pretending they're instructions and you'll see how stupid they would be if they weren't actually disguised "If... then..." sentences:
"Spare the rod, spoil the child." (It's not telling you to spare your rod and spoil your child is it?)
"Give an inch, he'll take a yard." (Again, is it advising you to give away inches?)
"You scratch my back, I'll scratch yours." (An obvious "If... then...")
"Nothing ventured, nothing gained."
"Waste not, want not." (OK, it could be telling you not to waste anything, but is it also just telling you not to be in want of anything? No. It's saying IF you don't waste anything, THEN you'll not want for anything.)
Obvious stuff, no?
So why does nobody put the obvious "If... then..." into "Feed a cold, starve a fever"?