Your Metabolic Engine
There’s no such thing as a 100% efficient mechanism, and the human engine is no exception.
When it comes to metabolic efficiency, the most efficient metabolisms extract calories and store them more easily, losing less of that energy as heat. A less efficient metabolism doesn’t extract calories as well and loses more of them as heat. If it’s fat loss you desire, then a LESS efficient metabolic engine is what you want.
Much of this metabolic efficiency comes down to genetics and metabolic hormones. For example, those with normal thyroid function produce more metabolic heat and are less efficient. Those with lower thyroid function produce less heat and are more efficient. This is one of the reasons those with low thyroid function respond more slowly to diet.
Certain parts of the body are more productive at storing fat and less efficient at losing it. These include the stubborn body fat areas like the hips, butt, and thighs of women, and the love handles of men.
These areas of fat are more insulin sensitive (more likely to store and less likely to release fat) and have more alpha than beta receptors. Betas are like fat burning garage doors. Alphas are like tiny kitchen windows; fat can barely squeeze through.
The Law of Metabolic Efficiency overlaps with the Law of Metabolic Compensation. Dieting makes the metabolism more efficient. That is part of what adaptive thermogenesis is doing. Annoying, I know. There are also things we’ve learned about macronutrients, toxins, and gut microbes that impact efficiency.
When it comes to macronutrients, not all calories are created equal: