Dry fasting seems to be the new trend in the alternative health community, I like it and find it very powerful, but don't think it's something that should be done without putting a lot of thought into it, and preferably maybe also having a decent diet beforehand, at least if it's a longer fast.
Yes, I agree, it is definitely a good idea to clean up the diet and do some various other forms of preliminary detoxing before diving into the fasting healing and detoxing modalities.
Fruit being the most healing of all foods.
Vegetables being healing but I feel that they are mostly healing in that they are just not as hard to process and Digest as many of the other foods such as Flesh and dairy and a lot of the grains.