There are many other hormones (besides thyroid hormone), proteins, and other chemicals that are very important for controlling energy expenditure, food intake, and body weight.
“Because all these substances interact on both the brain centers that regulate energy expenditure and tissues throughout the body that control energy expenditure and energy intake, we cannot predict the effect of altering only one of these factors (such as thyroid hormone) on body weight as a whole.
As a consequence, at this time, we are unable to predict the effect of changing thyroid state on any individual’s body weight” (American Thyroid Association).
