"Everything that is inside a contract is visible to all external observers. Making something private only prevents other contracts from accessing and modifying the information, but it will still be visible to the whole world outside of the blockchain."
Is there any other way to protect my private variables from being read/consulted by others ?
All contract data will store in Eth full node. Any data which is there in eth is public. But using access specifiers you can protect other contracts /node clients not to write or read data. Coming to geth will use Level DB for storing memory variables, state changes, block info..,
Most of the community experts will say don't save very sensitive data in public block chain.
You feel to save sensitive data in block chain encrypt data and save it. But its gives some level of data protection. But most of the blockchain architecture's I seen centralised server will hold sensitive data, and public/non sensitive data saving in blockchain.
