Why in the world would vampires be repelled by garlic?

Nothing, it’s a lie the vampires themselves set up so that they can rip your head for being an idiot with a string of garlic around their neck. Just saw “The Lost Boys” and it was epic. I didn’t know the vampire son is today’s Jack Bauer.

Garlic is a blood thinner, I think, so that may have something to do with it. Doesn’t make much sense though, wouldn’t vampires prefer thinner blood?

I would think onions, because it stung their eyes. But maybe, back in the movies when you pull out garlic and they flinched, maybe their eyes watered too much freshly cut onions were whipped out, so instead they say garlic. Eh, who knows.

Maybe because it stinks and tastes bad?

Garlic, because they wear it around their neck, and raw garlic tastes bad. Wasn’t that the original reason?

I’m with @Fiddle_Playing_Creole_Bastard, Its the blood thinning thing.

I think I came across a reference to some kind of allergic reaction they had to garlic, but I can’t remember where I saw it.

I guess garlic thins the blood and makes it less palatable for vampiric nutrition?

Oh. Well, I already know that it’s wrong. It’s movie fluff. But I want to know why…
How old is this belief?