The peel of the native Brazilian fruit jaboticaba is rich in anthocyanins, which are known for their anti-obesity effects in animal models. The aim of the present study was to evaluate the effects of freeze-dried jaboticaba peel powder (FDJPP) on a number of metabolic parameters in a model of diet-induced obesity. Mice (n 8 per group) were initially fed on a high-fat diet (HFD, 35 % w/w) for 4 weeks and then switched to a HFD supplemented with FDJPP (1, 2 or 4 % w/w) for an additional 6 weeks. Energy intake, weight loss, glucose tolerance, insulin resistance and lipid profile were determined, and the results were evaluated using ANOVA and Tukey's tests. The FDJPP exerted no protective effect on HFD-induced weight gain, hyperleptinaemia and glucose intolerance. However, the supplementation was effective to reduce insulin resistance, as evidenced in the insulin tolerance test, and subsequently confirmed by improved signal transduction through the insulin receptor/insulin receptor substrate-1/Akt/forkhead box protein pathway and by the attenuation of HFD-induced inflammation in the liver, verified by lower expressions of IL-1b and IL-6 and decreased phosphorylated IkB-a protein levels in all jaboticaba-treated mice. These results suggest that FDJPP may exert a protective role against obesity-associated insulin resistance.Key words: Jaboticaba: Obesity: Insulin resistance Obesity has reached epidemic proportions in the world, with substantial adverse consequences for human health (1) . A number of life-threatening diseases, such as type 2 diabetes mellitus, dyslipidaemia, CVD, hypertension and certain types of cancer, are associated with this condition (2) .Nutritional factors are known to play an important role in the development of a number of diseases. The recent changes in human lifestyle, with the introduction of high-fat/simple carbohydrate-rich diets, are amongst the most important factors leading to the increased prevalence of obesity. Conversely, epidemiological data suggest that increased consumption of fruits and vegetables are positively associated with the prevention of metabolic disorders, including obesity (3,4) . The ability of some vegetable-derived nutrients to reduce the risk of chronic diseases has been associated, at least in part, with the occurrence of bioactive non-nutrient compounds that are known to exert a wide range of biological activities (5,6) .Anthocyanins, which belong to the flavonoid class, are an example of such bioactive compounds. They constitute the largest and probably the most important group of watersoluble natural pigments responsible for the vivid blue, purple and red colour of many vegetables and fruits (7) . Many reports have shown that anthocyanin exhibits an array of pharmacological properties, such as anti-inflammatory and anticarcinogenic activities, as well as preventive effects on CVD and degenerative disease. The majority of research has focused on the antioxidant properties of these dietary polyphenols (8) . Furthermore, it has been shown that phenolic co...