The Doubtful Nature of “Luxuskonsumption” 1

Abstract

In 1911, and several times thereafter, Grafe and his associates (1) stated that the fasting, resting metabolism of an individual is not proportional to the surface area, but is significantly affected by the calorific value of the food previously ingested. They also postulated that the total metabolism is influenced in the same way by the total intake of energy. According to them, normal animals, including man, maintain a constant weight, almost without regard to the energy intake, and obesity is often nothing more than the failure of this alleged mechanism to respond normally to the stimulus of food. Finally, leanness is an over-response to a normal stimulus.They supported these views by the following type of experiments: A dog was starved for a long time, and its resting, fasting metabolism was then determined. This value was used as the basis for comparison. The dog was now offered an abundance of food, and gained weight rapidly. The metabolism was repeatedly determined in the fasting, resting state. The metabolic rate thus determined showed a progressive increase out of proportion to the increase in body surface. Table I sets forth their data in detail, rearranged by us.This increase in metabolic rate of the overfed animal beyond that of the starved animal was accepted by them as proof that the resting, fasting metabolism of the normal animal is increased by previous overfeeding. But the metabolic rate obtained after prolonged starvation should not have been accepted as a proper basis for comparison, since Schondorff (2) had previously shown that starvation caused a decrease I The expenses of this investigation were defrayed in part by a fund for the study of nutrition, created by

The Energy Metabolism of Man During Overfeeding

“…It is apparent that, in the series of experiments reported in this paper, surfeit feeding was not accompanied by any increment in basal energy metabolism. There was no evidence of even the small rise reported by Muller (191 I ) and by Wiley & Newburgh (1931). The results are even further out of line with the large changes recorded by Kleitman (1926).…”

Imbalanced insulin action in chronic over nutrition: Clinical harm, molecular mechanisms, and a way forward

“…Thus, the entire metabolic pathway from glucose, to caloric storage by DNL, to the eventual use of this stored fat by oxidation (obese humans and animals often do not reach that last step) is only slightly less efficient than the direct oxidation of glucose [383]. The speculation that the overfed body invokes metabolic mechanisms to burn away unneeded dietary calories was introduced in the early 1900s under the name 'Luxuskonsumption', but has been contradicted by this and other work [78,81,83,380,384,385]. For example, as long as DNL remains quantitatively minor, its short-term inefficiency is unlikely to significantly alleviate excess energy in the context of overeating a mixed diet [181,182].…”

Effect of Dietary Protein Content on Weight Gain, Energy Expenditure, and Body Composition During Overeating

“…The concept that when people overeat the amount of weight gain is highly individual has intrigued medical science for a century. [6][7][8][9] In a critical review of macronutrient composition and response to overfeeding, Stock 10 cites 12 studies in human beings to support the view that when people overeat a diet that contains either high or low protein, they are less "metabolically efficient" than diets of average protein intake. [10][11][12][13][14][15][16][17][18][19] This concept is appealing from an evolutionary perspective because the ability to waste "excess" calories when eating an unbalanced diet would ensure an adequate supply of nutrients while avoiding risks to survival as a result of excess weight gain.…”