Remember that if thermodynamicd our bodies was easy, then everyone would be walking around with a six-pack. The ironic conclusion is that the principle that weight gain on isocaloric diets must always be independent of macronutrient composition would violate the second law of thermodynamics. These are the three laws of thermodynamics, of how energy is transformed from one form to another. Do that for 30 years, and you will be 20 to 30 pounds overweight. The radiation constant is the product thermodnyamics the Stefan-Boltzmann constant and the emissivity constant for a material. If the surrounding air is even colder, being next to an ice cube will keep you warmer longer. The second law says that the entropy of the universe increases. If so, what biochemical mechanisms might plausibly explain it? I read it when it first came out, but never really had a place to put it. The ironic conclusion is that the principle that weight gain on isocaloric diets must always be independent of macronutrient composition would violate the second law of thermodynamics. It's not a bright picture. In general the pathways for gluconeogenesis that are required in order to supply obligate Weight loss law of thermodynamics e. The bulk of weight loss studies show that total caloric intake does correlate pretty well with weight loss, at least in the short term.
Login to your account. Open Peer Review reports The principle of "a calorie is a calorie," that weight change in hypocaloric diets is independent of macronutrient composition, is widely held in the popular and technical literature, and is frequently justified by appeal to the laws of thermodynamics. We review here some aspects of thermodynamics that bear on weight loss and the effect of macronutrient composition. The focus is the so-called metabolic advantage in low-carbohydrate diets — greater weight loss compared to isocaloric diets of different Weight loss law of thermodynamics. Two laws of thermodynamics are relevant to the systems considered in nutrition and, whereas the first law is a conservation of energy law, the second is a dissipation law: something negative entropy is lost and therefore balance is not to be expected in diet interventions.
Here, we propose that a misunderstanding of the second law accounts for the controversy about the role of macronutrient effect on weight loss and we review some aspects of elementary thermodynamics. We use data in the literature to show that thermogenesis is sufficient to predict metabolic advantage. Whereas homeostasis ensures balance under many conditions, as a general principle, "a calorie is a calorie" violates the second law of thermodynamics.
The recent awareness of an epidemic of obesity coincides with, and may have contributed to a dramatic increase in the popularity of a variety of low carbohydrate diets. This rapid switch in dietary habits of a significant part of the population, and the virtual revolution in the food industry, is unusual in that it stands in direct opposition to long-standing recommendations of the majority of the nutritional and medical establishment e.
Despite isolated examples, such as a recent editorial by Walter Willet pointing to the need to understand low carbohydrate diets [ 3 ], there is still little real acceptance by nutrition professionals or health organizations. One Weight loss law of thermodynamics of these diets that has been especially controversial is the so-called metabolic advantage — the idea that more weight may be lost calorie for calorie compared with diets of higher carbohydrate content.
We recently reviewed the literature on metabolic advantage [ 4 ]. We showed that there is a sufficient number of reports in the literature to establish the existence of metabolic advantage and we tabulated results from ten or so studies demonstrating that low carbohydrate diets can lead to greater weight loss than isocaloric low fat diets. The reports we cited have frequently been met with the criticism that the data could not be right because they would violate the laws of thermodynamics [ 56 ].
An example is the recent demonstration of metabolic advantage in a small, pilot study [ 7 ] which, despite its preliminary status, was extremely well controlled. This work received a good deal of attention in the popular press. Media reports, however, included comments of experts that "It doesn't make sense, does it? No one has ever found any miraculous metabolic effects. If this is an accurate quotation, it is odd indeed. Miraculous, or otherwise, a metabolic effect was found.
In the absence of an identifiable methodological Weight loss law of thermodynamics, experimental data has to be accepted and numerous investigations, in fact, serve as precedents for Greene et al. In our previous review of metabolic advantage [ 4 ] we showed that there is, in fact, no theoretical violation of the laws of thermodynamics, and we provided a plausible mechanism. In general the pathways for gluconeogenesis that are required in order to supply obligate glucose e.
Here, we simplify the thermodynamic argument and review some of the relevant principles. We show, moreover, that well-established data in the traditional nutritional literature predict metabolic advantage and no one should be surprised. Weight loss law of thermodynamics ironic conclusion is that the principle that weight gain on isocaloric diets must always be independent of macronutrient composition would violate the second law of thermodynamics.
Weight loss law of thermodynamics
As the most basic level, losing weight is all about creating a caloric deficit. I've spoken about this many times - if you're burning more calories than you are. 1st Law of Thermodynamics The First Law of Thermodynamics simply states that energy can be neither created nor destroyed (conservation of energy). Jul 28, · We review here some aspects of thermodynamics that bear on weight loss and the role of the second law shows that differential weight loss is not. Low carbohydrate diets in particular have claimed a "metabolic advantage" meaning more weight loss than in weight loss. The laws of thermodynamics are silent. This is generating many comments, see below for an update! Behind the scenes some skeptics are suggesting that CO2 can’t warm us because the atmosphere is colder.