Determinations of basal metabolism are widely used in the clinical study of obese patients, apparently in the expectation of arriving at some understanding of the underlying disturbance. Von Noorden1 classified obesity as exogenous and endogenous and defined endogenous obesity as characterized by a lowered metabolism or, as he called it, "Verlangsamung der Zersetzungsenergie der Zellen." He stated that obesity of the endogenous type is rare. Since hypofunction of the thyroid gland is associated with a depression of the basal metabolism, the conclusion is frequently drawn that a low basal metabolic rate in an obese person is indicative of hypothyroidism.
The term basal metabolic rate is ambiguous, and its inconsistent use has caused much confusion. Many authors designate by basal metabolic rate the percentage deviation of the observed value from some normal standard. The most widely accepted standard uses surface area as the unit of comparison. In numerous clinical papers