10/04/2012 08:09 am ET Updated Dec 04, 2012

Getting the Lowdown on Your Metabolism

Have you worked out every single day since Labor Day, eaten a healthy, well-proportioned diet and still haven't lost a pound? There are two things I want you to know: 1) You are not alone, and 2) it may not be your fault. Isn't that the best news you've heard all day?

Often, we feel as though weight loss is just not in the cards for us, or that it is utterly impossible. You need to understand a few things about the mysteries of our bodies and why you and a friend might eat the same diet, work out the same amount, live identical lifestyles and still achieve different weight-loss results. One may lose 10 pounds, while the other not only maintains their weight but even gains a pound. Contrary to popular belief, this scenario doesn't always have to do with genetics. It may be your metabolism that's keeping you from achieving your goal.

The point is, the resting metabolic rate, or RMR, is dramatically different from one person to the next and can deeply affect how and why a person may gain or lose weight. RMR is the rate at which your body uses energy when you're at rest. It measures energy use for basic bodily functions like circulation, breathing and digestion. Sixty-five to 75 percent of a person's energy is expended at rest without taking into account the energy it takes to walk, talk, work or exercise.

Now it may make more sense to you why it often seems that only adding exercise to your routine, without making any dietary adjustments, often leads to diminished results. Remember, three-fourths of your energy is expended before even moving a muscle, so exercise alone is only touching upon a small portion of calorie usage.

It's important not to forget about exercise, of course, since a good exercise program is an essential part of the weight-loss equation. It can eventually speed up your RMR and accelerate weight loss in the long run. But for people with a slow metabolic rate (which can be detected through clinical tests), less energy is burned overall, regardless of calorie intake and exercise. I'm sure you and your friend have experienced this when you are both following the same diet and exercise routine and you attain completely different results. This may mean one of you has a slower metabolism, making weight gain more common and weight loss much more difficult.

What I suggest for people who are struggling to see results is having a fairly simple and very accurate test performed that can be done at a center like my own in Naples, Fla. and in similar medical practices across the country. The test involves a hand-held device that doctors can use right in their offices. The patient simply breathes into a tube for 15 minutes as the machine calculates their individual metabolic rate.

Understanding your metabolism can save you frustration and prevent lackluster results when it comes to weight loss and maintenance. Metabolism testing can identify ones struggle with losing weight, but also serves as an extremely important marker of other serious factors that can drastically affect one's overall health. Among them are some of the most frequent conditions seen in Americans today, including diabetes (Types 1 and 2), hypertension and hypothyroidism (an underactive thyroid). Therefore, not only is this test valuable in detecting a slow metabolism that's hindering weight loss, but it more significantly serves as an indicator of other potential major medical issues that may need to be addressed.

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