INS and obesity due to melanocortin 4 receptor deficiency: However, in another study, after an 8 h time-refrained feeding (ad libitum feeding between 10:00 and 18:00, water fasting between 18:00 and 10:00) for 12 weeks, the fasting glucose of adults with obesity showed no significant changes, and the insulin and HOMA-IR of the participants decreased, although not significantly [13].