Can I switch the boxes’ order? 22 February 2022 07:13 No, you should not switch the boxes' order, as each day of ProLon has a precise caloric and nutritional balance. Related articles Is tea, coffee or infusion allowed during ProLon? Can I have a nutritional support? Can I replace a food or ingredient with another? Can I chew gum during ProLon®? What is the ProLon® Fasting Mimicking Diet® program?