Not only can you use the pulp leftovers, but you should also be doing it! While juicers for greens tend to preserve as many nutrients as possible, fibers do not survive the process in large amounts. Centrifugal juicers are known to break down a lot of fibers, while masticating juicer units leave some of the fiber in the juice. To overcome this small downside, all you have to do is open up the juicer after you are done, and put some of the pulp back into the juice. Friendly advice – start small and see how your body responds to the pulp. If you overdo it, you will have a glass of sauce, not a glass of juice, and you will be needing a spoon.