Homéostasie énergétique et métabolisme glucido-lipidique : pourquoi deux substrats différents ?

Two nutrient families mainly ensure covering human energy needs: carbohydrates and lipids, even if proteins are also involved, while in a particular way. Paradoxically, energy storage is mainly based on lipid deposition in adipose tissue. Carbohydrate oxidation represents a substantial part of energy metabolism, while human beings cannot synthesize glucose from lipids. In fact, the respective properties of these two families of substrates are very complementary, in term of metabolism and energy supply, according to metabolic status, either physiological or pathological. Each of these substrates could represent an advantage or a disadvantage depending on rate and/or efficiency of ATP synthesis. The comparison between these two pathways with their respective characteristics is particularly interesting when considering the today's diseases related to excess of nutrient supply of either carbohydrates and or lipids.