In the present study, despite all animals receiving the same amount of dietary fat, we found higher contents of glycine conjugates in the obese mice and higher content of sulphate and glucuronic acid conjugates in the lean mice, supporting diverging roles of these conjugation pathways with regard to body composition. We have previously Adaptaquin reported that mice fed the hydrolyzed casein diet had reduced fed state plasma concentrations of glucose and insulin relative to those fed the intact casein diet. Moreover, fed state plasma concentration of the glucose catabolism marker lactate was lower, which, together with a tendency toward reduced respiratory quotient during the light phase, strongly indicated less usage of glucose as an energy substrate in the mice fed hydrolyzed casein as compared to those fed intact casein diets. NMR-based metabolomics confirmed reduced glucose and lactate concentrations in liver and plasma, whereas hepatic AbK glycogen concentration was higher in mice fed the hydrolyzed casein as compared to those fed intact casein diets. Together, our results strongly indicate a shift from usage of carbohydrates as energy substrate through glycolysis towards alternative metabolic usages of glucose, including storage as glycogen. Interestingly, in the body glucose can be metabolized to UDP-glucose, which subsequently can be used either in the synthesis of glycogen, or be further metabolized to D-glucuronic acid. Our LC-MS analyses in the present study suggest that more glucose was converted to D-glucuronic acid, facilitating Phase II conjugation and urinary excretion of glucuronic acid conjugated compounds. Such a redirection of glucose from glycolysis could also potentially remove substrates used in de novo lipogenesis. We therefore measured liver lipid contents and hepatic gene expression levels of enzymes involved in de novo lipogenesis. PCA scores and loadings of these data showed that mice fed hydrolyzed casein were characterized by a decreased expression of genes involved in de novo lipid synthesis and decreased content of free fatty acids and triacylglycerols. As shown in Fig. 4C�C4F, expression of lipogenic genes, Acaca, Fasn, and Scd1 ) was significantly decreased after feeding with hydrolyzed casein, indicating that de novo lipid synthesis was repressed. Furthermore, liver free fatty acids and lysophosphocholine were reduced in mice fed hydrolyzed casein relative to those fed intact casein diets, while a significant effect on the content of steryl esters and triacylglycerols could not be established.