You want to use fresh squeezed lemon juice because it has the enzymes needed to cleanse your system. The problem with packaged/processed lemon juice is you don't know how long it has been in the bottle and you don't know if the enzymes are still active. If you are going to be going through all this trouble and basically starving yourself, you want to achieve the best benefits. There really is no cutting corners with the MC. It is straight-forward and simple. And plus, it will probably be cheaper to squeeze your own lemons. Good luck!