Appetite regulation would be one, but that wouldn't explain studies in which food intake is strictly controlled. Metabolism regulation, insulin/glucagon regulation, intestinal flora, digestive efficiency, and other factors would certainly affect overall body mass.
And issues such as thyroid function do directly affect metabolism.
Appetite regulation would be one, but that wouldn't explain studies in which food intake is strictly controlled. Metabolism regulation, insulin/glucagon regulation, intestinal flora, digestive efficiency, and other factors would certainly affect overall body mass.
And issues such as thyroid function do directly affect metabolism.