Hello.
There are three Canadians in my year that I can think of, though we're just going into fifth year now so I don't think any of them will actually be around by the time you get here. One - who is a good friend of mine - was a grad when he started here; the other two were some of the youngest in the year when they started (only 17), so definitely not gap year students. They're all perceived as lovely, but I think that's more because they're nice people than particularly because they're Canadian.
Besides Canadians, there are loads of other international students here (as there are at most medical schools, I think), so you definitely won't stick out like a sore thumb or anything. Hope that helps a bit!