"Jak jest twoje zdrowie?" sounds totally wrong to me, although I understand perfectly why you wrote that. It's hard to say if there is some verb implicit here. I guess you should just remember this as a construction which is a bit ungrammatical.
Conversation-wise they do not look the same to me... I think the Polish sentence should at least be "A jak twoje zdrowie?" to express the "What about your health?" which doesn't sound like it can be the first question in a conversation.