Abstract

Macronutrient metabolism is essential for transferring energy contained in food to usable forms of cellular energy. The balance between energy from fuels flowing to cells and then expended during cellular work will determine body size. In the last decades, energy homeostasis has been challenged by an overwhelming dietary macronutrient availability that imposes a need for expanding adipose mass. The capacity to handle such higher energy and macronutrient fluxes impacts metabolic processes at the cellular and whole organism levels. Herein, we reviewed carbohydrate, fat, and protein metabolism, particularly comparing individuals with and without obesity.