A comment on the practice of expressing food and water intake as a proportion of body weight.
It has been a common practice to express food and water intake as a proportion of body weight in an attempt to control for weight differences between individuals or treatment groups. It is argued here that, unless extreme caution is taken, this procedure is likely to result in misleading conclusions. Intake per kilogram body weight is not simply a measure of intake and it should not be treated as though it were. Furthermore, use of this technique to measure ingestion is more likely to introduce spurious relations between consumption and body weight than it is to eliminate relations which are actually present. We feel, therefore, that this measure should, at most, be used as a supplement to raw measures of food and water intake.
D000375:Aging; D000818:Animals; D001835:Body Weight; D004326:Drinking; D004435:Eating; D004734:Energy Metabolism; D007031:Hypothalamus / Q000502:physiology; D009482:Neurophysiology / Q000379:methods*; D051381:Rats