Why Are We Overweight? Part 9

I have previously described an inherent system that has evolved to regulate the amount of energy we ingest and expend. The hormones insulin and leptin are primary players and when they are not circulating in our blood (for example, if we have not eaten lately), their absence results in a feeling of hunger and the desire to be physically active. This is logical because hunting for and ingesting food is precisely what is required to ensure survival under these circumstances (i.e., when energy expenditure exceeds intake and a negative energy balance prevails). Conversely, after we eat and have more energy than we need, these hormones circulate to store the fuel we’ve taken in and also discourage us from eating more. The end result is homeostatic control that should work like body temperature regulation: Body fat should be maintained at a ‘set point” from which dramatic deviations would be unlikely.

Homeostatic regulation of energy balance by insulin and leptin is well suited for a lifestyle where a negative energy balance is the prevailing condition. But when a positive energy balance is the norm, the system loses its effectiveness. First off, if we have more energy than we need, the urge to hunt will be absent. This will dampen the desire to be physically active, which is what is required to keep fat from accumulating when we eat more than we should. Furthermore, the presence of these hormones in circulation more often than should be the case and in larger quantities results in desensitization of the receptors that they activate. This means that the desire to eat might not be removed even though there are plenty of messengers telling us that it should be. The inability of these hormones to exert their influence also results in more fuel staying in our blood. This is why excessive insulin production (hyperinsulinemia) creates the poor glucose control that characterizes type II diabetes and is a major contributor to metabolic syndrome, a disease that is growing in prevalence at an alarming rate. 

We are in a positive energy balance now more than we should be because procuring food costs only a fraction of the energy that it used to. Furthermore, we now derive many rewards from eating that the system is not designed to counter. This means that we cannot simply trust our intuition with respect to how much we take in because if we do, it’s a sure bet we’ll ingest more than we need and wind up increasing our fat stores to unhealthy levels. Instead, we have to use our intelligence and the process begins with determining your specific caloric maintenance level.

Many people spend much thought coming to conclusions regarding specific foods that are making us overweight or contributing to our diseased state. Quite often, this is analogous to putting the cart ahead of the horse. Before you make decisions as to how to allot the energy quota that suits your purpose (i.e., how much protein, carbohydrate and fat you are going to take in), you have to determine what your specific quota is. And although many formulas exist that are designed to give you that information, a high degree of inter-individual variability renders such estimates ballpark figures at best. The tried-and-true method for determining your caloric maintenance level is to eat the same amount of calories each day for several weeks while maintaining your typical activity level. If you weigh the same after the trial period as you did before, you’ve got your magic number. If not, simply adjust your intake in the appropriate direction and try again. Eventually, through trial and error, you’ll determine how many calories you currently need. 

Being that your caloric maintenance level is the amount of energy you need to maintain your present fat stores, once you know this number, you can adjust your intake accordingly based upon your objectives. For example, if you currently need 2500 calories each day to stay as you are and your desire is to lose fat, you could reduce your intake to 2000 and, theoretically, drop a pound in a week. This is because cashing in a pound of fat liberates 3500 calories of energy in your body. Now, once you know the number of calories you’ll be taking in each day, you can then determine how many of them should be provided by each of the macronutrients mentioned above. And believe it or not, even if you decide to take in a large percentage from carbohydrates, at this point, you’ll still lose fat because your energy intake level ultimately determines how your energy stores are affected.

Operating below your caloric maintenance level will cost body fat because the shortfall has to be accounted for. But establishing the deficit need not be done as I have described. Instead, you could opt to continue ingesting 2500 calories per day and set up your deficit by increasing the energy you use. For example, when a 175-pound person walks four miles-per-hour, they expend approximately six calories each minute. Consequently, an hour-long walk at that pace each day added into the mix would ensure the loss of a pound of fat in less than two weeks without having to eat any less. Obviously, this is the better alternative for health, fitness and long-term success.

This article was originally published in New Living Magazine, which can be accessed on-line at www.newliving.com.





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