Direct Measurement of Food Intake in Man: A Method for the Objective Study of Eating Behavior

A method for the direct measurement of food intake in man is described. This method provides a means for independently studying many of the variables which are thought to operate in the control of food intake. A liquid diet from a hidden reservoir was ingested through a straw during a 20-min. breakfast or lunch meal. Subjects were tested at the same time each day for several weeks. Stable ingestion patterns emerged after four or five trials. The ingestion of a constant amount of liquid diet at various intervals before the test meal depressed intake as a function of the time interval. Subjective hunger ratings correlated well with rate and amount ingested and were reduced appropriately by ingestion prior to the test meal.