Yes, this is sometimes needed. The microbiome is a relationship between microbes and an individual's immune system as dictated by genetics. All life strives to adapt and survive. Sometimes the first program creates a 60% improvement, and then an improved equilibrium is established. If symptoms persist, another round may be warranted. If symptoms are reduced, but not gone, then a repeat performance is often best done 4-6 months later because the immune system needs some time to reestablish a new relationship. In this program we're helping Nature, not dictating, thus the gains are more genuine and enduring. However, as in all things with the body— biochemical individuality is the rule and acquired pathogens introduce new competitions. Dietary improvements are hugely important. The program is a quick "leg up" the ladder and a huge boost forward in the process of improving and maintaining optimal health.