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View Full Version : Thermodynamics, Conservation of Energy, and weight loss.


Serapium
Nov 20, 2011, 11:49 AM
So my wife has been doing the HGC diet, taking HCG orally twice per day and consuming a total of 500 calories (good calories- lots of raw veggies and some chicken, red meat, or fish for protein). She weighs 174 pounds currently and wants to drop to 145.

She also exercises regularly, teaching a latin dance fitness class for one hour at a gym five days per week.

What has me stumped is that she has been on this diet for three weeks and has lost only a total of 1 pound.

I understand the body going into starvation mode, that the metabolic system slows down to conserve energy, but what I don't understand is how her experience is even remotely possible according to the laws of physics.

The human body converts mass into energy to power our muscles, our nervous system, etc. Just by sitting completely still and breathing regularly for eight hours (sleeping, for instance) the various muscles that power your lungs and heart, plus and the energy required by your nervous system burns about 549 calories in an average 160 lb person according to several sources that I found.

So, even if a person does absolutely nothing in a given day, their system burns roughly 1500 calories (I'm not making an effort to be mathematically precise - the issue is more general than that). Let's say that the body, when going into conservation mode, has the ability to reduce the total caloric need by 30%. That means that her body is burning somewhere around 1000 calories just to keep oxygen circulating through the body. Add to that the fact that she's exercising, moving around during the day doing household chores, taking the kids to and from activities in town... hell, walking back and forth to the bathroom... she HAS to be burning at LEAST 1500 calories in a given day.

So, since she is only consuming only 500 calories a day and not losing weight (regardless of hcg being present or not), where is the extra energy come from?

ebaines
Nov 28, 2011, 11:05 AM
The purely thermodynamics answer is that there is no extra energy coming from anywhere. If in fact your wife is consuming only 500 Calories/day then unless she is in a coma she is burning fat to maintain metabolism. So if there is no weight loss that must mean that weight is coming from somewhere else - perhaps water retention?