If you are worried about your reserves you could do some shorter fasts to begin with, 2-3 weeks or whatever you feel comfortable with then break these fasts correctly with whole raw foods for the same amount of time you fasted for. Post fast your body will absorb nutrients better than ever and if you give it the best quality raw foods you can you will certainly be able to build your nutrient levels to what the body needs fairly quickly. Your body will also begin at least any healing it needs done in those times and you will be stronger for your ultimate attempt to fast to completion as well.