The Insular Cortex (IC) is implicated in the integration of sensory, emotional, and cognitive aspects of feeding behavior, supported by its strong connectivity to extensive brain regions. This study explores the IC’s role in modulating adaptive feeding behaviors and taste aversions through a series of behavioral experiments on C57Bl/6 mice, comparing IC loss-of-function and control groups. Initially, adaptive feeding tests with high fat and high sugar diets indicated a tendency for a reduction in high-sugar diet intake in IC lesioned mice, suggesting altered post-ingestive feedback. Expanding on this, subsequent two-bottle tests (TBTs) with sucralose (non-caloric sweetener) versus water, followed by sucrose (caloric sweetener), showed no significant preference differences in lesioned mice compared to controls. However, in tests comparing sucralose and sucrose, the lesioned mice displayed a tendency for reduced preference for sucrose, implying disrupted post-ingestive sugar feedback. Another behavioral paradigm, the Conditioned Taste Aversion (CTA) test further highlighted the IC’s involvement in taste and visceral pairing, with lesioned mice exhibiting attenuated aversion to aversive stimuli, specifically in the NaCl intake tests. The quinine test, intended to assess the natural taste avoidance of a bitter tastant was not indicative of any changes in avoidance behavior between controls and lesioned mice. Through multiple behavioral experiments, our results suggest that medial IC lesion does not affect the sweet-tasting, but disrupts the post-ingestive signal from caloric sugar. Moreover impaired CTA acquisition and retention indicates the integration of gustatory and visceral signals are interfered by IC lesion and thus, appropriate feeding decisions cannot be made. Therefore, we conclude that the medial IC contributes to the dietary preferences and intake behaviors via mediating and integrating post-ingestive feedbacks.