Background: Malnutrition and accessible high-quality protein food sources are two of the world’s alimentary challenges. Edible insects are nowadays recognized as a possible functional food solution with lower environmental impacts and beneficial health effects. Objective: In this context, the aim of the present study is to evaluate Madagascar cockroach (Gromphadorhina portentosa) flour supplementation effects on a malnourished mice model, considering its effects on metabolism, adiposity, and inflammatory liver profiles. Method: Male Swiss mice are divided into five groups and fed with experimental diets for eight weeks, including a standard diet (ST) ad libitum, AIN93 ad libitum (AIN), insect flour-enriched AIN93 (AIN+IM), AIN-40% feed restriction (AIN-FR), and insect flour-enriched AIN-40% of feed restriction (AIN-FR+IM). The metabolic profiles, adipose tissue, biochemical parameters, and liver IL-6 and IL-10 expression are evaluated. Results: The main findings show a body weight and metabolism improvement followed by an increased recovery of the adipocyte area in the AIN-FR+IM group when compared to the AIN-FR malnourished group. Reduced hepatic IL-6 and increased IL-10 expression are also detected in the AIN-FR+IM group. Conclusion: The results show that insect flour supplementation enhances both body weight and adiposity gain/recovery. The results also show hepatic improvement of inflammatory markers.