Metabolism Explained

Diabetes targets overweight people

(DGIwire) —  When trying to determine the best diet for a lean healthy body, people often wonder, “Exactly what is metabolism?” or “What is base metabolic rate (BMR)?

Metabolic rate is simply the number of calories you burn in a given period of time. This is what most people generally refer to as metabolism.  A calorie is just a simple measure of heat energy and the number of calories you burn in a day, your metabolism, will be a cumulative amount based on many factors including your current body composition, activity level and many other factors.

Body composition is important because the metabolic rates in different parts of the body are not the same.  Some parts like the brain, muscles and some organs use more calories than others.  You have active tissues and less active tissues.  Even when you are resting, your heart, brain, kidneys and liver are responsible for over 80% of the calories used while fat and bones consume a small percentage.  Muscles are not the main calorie burners and at rest don’t use as many calories as most people think.

Measuring metabolic rate is not as simple as it seems.  It is the sum total of thousands of complex chemical and hormonal actions.  It also is influenced by age and to some degree by genetics.  However, what you need to understand is that lean body mass (LBM), which includes everything except your body fat, is what generally determines the amount of calories you use each day.

“Many people think that increasing muscle mass will dramatically increase metabolism.  However, although increased muscle mass will increase your base metabolic rate (BMR), the effect is less than you may have been led to believe.  Conversely, losing muscle mass will result in a lower BMR, but probably not as much as you think.  The real problem with the loss of lean body mass, common in most diets, is that it triggers primal survival mechanisms that result in increased and often extreme feelings of anxiety and hunger,” according to Dian Griesel, Ph.D and Tom Griesel, co-authors of TurboCharged: Accelerate Your Fat Burning Metabolism, Get Lean Fast and leave Diet and Exercise Rules in the Dust .

Obese people actually have a higher BMR than lean people because they have a lot more overall tissue.  Eating and to a lesser degree what you eat, can also raise metabolic rate since the body uses energy to digest and assimilate foods.  Metabolic rate or BMR calculators only provide an average compared to many people who have similar height, weight and activity levels.  These estimates can be under or over by much more than people think.

Griesel adds, “Worrying about your metabolism slowing down or trying to increase it dramatically is really a waste of your time.  The most important thing is to keep the focus on improving body composition and overall health.  Take any and all actions that will help accomplish these two objectives and you can’t go wrong. Body composition and health will continue to improve over time with the right food, activity and lifestyle choices.  You will be able to maintain an awesome looking and feeling body with little additional effort.”