Juice fasts, whether homemade or store bought, are not a healthy or effective solution to losing weight or staying healthy in the long term. Yes, they do temporarily supply your body with a burst of vitamins and minerals, but they do not furnish you with protein, fats or fibers, which are necessary for health. Most fruits and vegetables lack substantial amounts of fat and protein, and the liquid form of vegetables lacks much of the fiber content that aids in normal digestion. Lastly, the high sugar content of juices (even homemade) is not an appropriate source of nutrition and may tamper with the natural sugar levels in your blood. On the other hand, occasionally drinking liquefied vegetables/fruits as a supplement to a regular and healthy diet can do no harm!