Diet-Induced Termogenesis (DIT)

DIT refers to the amount of energy required to absorb, process and store nutrients and accounts for an increase in energy expenditure (EE) with respect to postabsorptive state [30]. Moreover, DIT depends upon the amount of substrate supply and disposal, and it is different among the different substrates. Jequier [30] investigated the thermic effect of nutrients. The authors found that when given intravenously, glucose (under euglycemic-hyperinsulinemic glucose clamp condition) induces an increase of EE of 7% of energy infused, whereas lipid infusion stimulates EE by 3% of energy infused. The stimulation of EE due to amino acid infusion in depleted patients is 30-40% of the energy infused as amino acids. The cost of nutrient storage for glucose was 12% of the energy content of the stored nutrient, while it was found to be 4% for lipids [30]. Eventually, as far as lipids are concerned, it has to be taken into account that the cost for the oxidation/storage of MCT is significantly higher when compared to palmitate [31], as the former need first to be elongated and then they can be oxidated.