I was so lucky because this shop was located almost opposite of my hotel!
It is very, very small - you can hardly move - but it is surprising how much they have on offer on such a small space. I bought spreads, soy milk (banana and vanilla flavors), yoghurt and carrot juice. And there is much, much more, everything you expect from a health food store.
Service was friendly and English was spoken.
The nearest tram and metro stop is Corvin-negyed, it's only a few metres down the road from there.
Cons: Very small