For my protein, I prefer to mix with OJ (about 100 cals), and generally speaking, I like juices standalone--a couple swigs of OJ/Pineapple hits the spot. What is reason for only drinking coffee/water--again, is this only because of calories?

Along the same lines, I also have a juicer that was gifted to me, which extracts from pretty much everything, veggies, fruit; is this 'bad', or is there some reasoning not to use it aside from calorie content? I've heard so much on both sides, but nothing really definitive beside personal preference. If you eat the fruit/veggies anyway, is juicing a decent alternative? Any empirical evidence, or just anecdotal?

Thanks for the help.