Say what?
The
MBR only stores the boot sector which the BIOS uses to start the process of loading the operating system. I.e. the MBR doesn't record or store data.
If you're losing data this could be the sign of a failing hard drive, but before making any assumptions I think you need to post some more info.
Give us a more detailed description of the problem you're having
your system specs
what operating system you have installed
