(redirected from caloric requirements)
Also found in: Dictionary, Thesaurus, Medical.


Obsolete a hypothetical elastic fluid formerly postulated as the embodiment of heat



a hypothetical substance (weightless fluid) representing heat by whose presence in bodies scientists of the 18th and early 19th centuries attempted to explain observed heat phenomena, such as the heating of bodies, heat exchange, thermal expansion, and thermal equilibrium. The caloric theory required that certain unusual properties be ascribed to this fluid, for example, weightlessness, an elasticity greater than that of all other substances, and an ability to penetrate and expand the tiniest pores of bodies. In the 18th century, scientists hypothesized the existence of weightless fluids besides caloric, among them phlogiston, to explain the physical and chemical properties of substances. Only at the beginning of the 19th century was it conclusively proven that heat phenomena are caused by the chaotic movement of atoms and molecules. An important role in refuting the caloric theory was played by the experiments of B. Rumford (1798) and H. Davy (1799) that proved that the heating of bodies can be brought about by mechanical work.

References in periodicals archive ?
As indicated in Table 2, neither group's caloric requirements were fully met during the study period; however, the standard deviation for both groups was large and there were individual instances of participants receiving 100% of their prescribed calories on certain days.
PHILADELPHIA, June 28, 2013 /PRNewswire-USNewswire/ -- For the first time, researchers investigated enteral nutrition and caloric requirements (CR) among critically ill children in a new report published in the Journal of the Academy of Nutrition and Dietetics.
Our only manufacturing energy requirements are our own personal caloric requirements.
Fitness starts with balancing individual caloric requirements with calories consumed and calories burned," said Collins.
Commercial meals are better matched to the general population's nutritional and caloric requirements.
Nutrient density -- or enjoying more foods that are rich in nutrients first and selecting less nutrient-rich options as caloric requirements and physical activity levels allow -- is a long-standing nutrition principle that was also a cornerstone of the 2005 Dietary Guidelines for Americans, which were released in January.
This is a natural protective mechanism that the body uses, mediated by a change in thyroid hormone production that reduces the body's caloric requirements.