What does "ya" mean in this sentence?
"Como ya sabemos la carne es una fuenta importante de hierro." Does this sentence translate as "As we already know, meat is an important source of iron." or "As we now know, meat is an important source of iron."?
I agree with wataya. When you say 'Como ya sabemos' / 'As we already know' you are talking about something that has been known for a long time, perhaps something that is obvious or should be obvious. On the other hand, when you say 'Como sabemos ahora' / 'As we now know', then you are talking about something that only recently became known, something that had been unknown for a long time.
I'd translate it as 'As we already know'. 'As we now know' probably would be sth. like 'Como sabemos ahora,...'.
Both translations accurately reflect a proper statement in English. They both have the same meaning. However, "As we already know..." is closer to the literal translation from the Spanish statement.