My iPhone is jail broken, how to update the IOS software?

My iPhone 4s with ios 5.01 is jail broken, so I have some question:
1- Can I update my software to IOS 7 without losing my data by back up for apps and contacts?
2- If Q 1 is possible so how?
3- If I must lose the data & apps, how can I do this update safely and get raid of the jail break?

Any answer will be appreciated even if it's not helping, Thank you.

Sorry, you're gonna have to reset your phone to update.

When you update your ios, cydia and all jailbroken features will be erased from your phone, but the rest of your apps, music, and pictures will not be affected. If you don't feel comfortable doing it, back up your phone's contents to icloud or your computer first so that you can restore it if anything goes wrong. Sadly, there isn't a way that I know of to save your jailbroken contents, so you will have to redownload things if an ios7 jailbreak comes out.
Hope that helped.
(edit, I updated from ios6 instead of 5, so I'm not sure if it's the same, it would definitely be good to back up your phone just in case)

Well. Yes and No. You can reverse the OS modification (jail break) … But only if you backed up your original. If not then no. Each phone OS is coded to that phone. That is what used to verify that your phone is genuine. You can wait till someone modifies IOS7, But that may take a while. Unfortunately that's one of those risks you take for OS mods. If you did back up by any chance. The process is same you did for OS mod. Once you have loaded your original OS, then you can update to new OS. As far your data, I'm pretty you can back up your data to icloud. But before you reverse the OS mod. Back up to pc and see what you can load back phone. You should be able to recover 99% of data.