Hello, you are probably a bit wrong about pronunciation, usually at the feast, russian people says "za zdorovye" not an "na zdorovye". The difference between that two sentences is when russian people says "na zdorovye" they want to show their gratitude for gratitude. "Na zdorovye" means "You're welcome".
— Can you give me a glass please, I want to pour vodka.
— Na zdorovye!
So, let's talk about "za zdorovye". This is the usual toast, which says Russian people. Actually thats looks pretty strange because "za zdorovye" means "I want to propose a toast to health and prosperity". I mean alcohol negatively affects the health, how can we drink for it? But this is absolutely normal in Russia and no one gives it value. :)
You know, in the company of my friends we almost always drink with words:
And it is kind of funny as hell. 140
I've heard numerous times that the stereotype stemms from the fact that during the cold-war period Russians were commonly played by other slavs in American movies. Among them were the Polish, who allegedly say "Na zdrowie" when they drink. So at some point things got mixed up.
I'm not sure if it is a valid explanation, but it does sound legit
We never say "Na zdorovye" when toasting, but we never say "Za zdorovye (full stop)", either. You need to specify. The toast usually goes like "(Давайте выпьем) за здоровье родителей юбиляра" = (Let's drink) to the health of the hero of the day's parents.
Another popular toast is "Будем здоровы" = Let us all be in good health.
Потому что "nazdrovye" это попытка прямого перевода "cheers". У нас в культуре такого слова нет, которое мы просто произносим, чокаясь, вот иностранцам и пришлось худо-бедно адаптировать.