To summarize, food intake is influenced by metabolic activity in hypothalamic neurons and elsewhere; by hormones that signal the body's fat content to the brain; and by other homeostatic-need situations such as low blood glucose. All of these represent instances of negative feedback.
Well because it is the amount that the nutritional facts are given on, say you buy a box of donuts, and it says 80 calories that could be for a 2 donuts for 1 for the whole package but knowing the serving size you can base how much you eat etc
False because people wouldn't want to gain weight faster.
A low amount of calories or no calories