For privacy reasons, Health data only gets included in iTunes backups if you enable encrypted backups. It also gets included in iCloud backups (there was some confusion about whether it's included in iCloud backups but it definitely is), so you need to restore from either an encrypted iTunes backup or an iCloud backup
If you don't have either of those and you still have your 6 then do either an iTunes encrypted backup or an iCloud backup and restore from that. If you don't still have your 6 then your data no longer exists and can't be restored
See here for more information:
http://support.apple.com/en-us/HT203037