CONCLUSION
TOP
ABSTRACT
INTRODUCTION
THERMODYNAMICS
METABOLIZABLE ENERGY
ENERGY EXPENDITURE
IS A CALORIE A...
OTHER EXPLANATIONS FOR...
CONCLUSION
REFERENCES
We conclude that a calorie is a calorie. From a purely thermodynamic point of view, this is clear because the human body or, indeed, any living organism cannot create or destroy energy but can only convert energy from one form to another. In comparing energy balance between dietary treatments, however, it must be remembered that the units of dietary energy are metabolizable energy and not gross energy. This is perhaps unfortunate because metabolizable energy is much more difficult to determine than is gross energy, because the Atwater factors used in calculating metabolizable energy are not exact. As such, our food tables are not perfect, and small errors are associated with their use.
In addition, we concede that the substitution of one macronutrient for another has been shown in some studies to have a statistically significant effect on the expenditure half of the energy balance equation. This has been observed most often for high-protein diets. Evidence indicates, however, that the difference in energy expenditure is small and can potentially account for less than one-third of the differences in weight loss that have been reported between high-protein or low-carbohydrate diets and high-carbohydrate or low-fat diets. As such, a calorie is a calorie. Further research is needed to identify the mechanisms that result in greater weight loss with one diet than with another.
ACKNOWLEDGMENTS
ACB and DAS shared the tasks of drafting and revising the manuscript.
REFERENCES
TOP
ABSTRACT
INTRODUCTION
THERMODYNAMICS
METABOLIZABLE ENERGY
ENERGY EXPENDITURE
IS A CALORIE A...
OTHER EXPLANATIONS FOR...
CONCLUSION
REFERENCES
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