Healthy Genes or Healthy Living?
When we talk about metabolism, it’s often a complaint: “I wish my metabolism let me binge on potato chips and pizza like my friend and not gain weight.” The reality is that we all have some kind of metabolism, and almost everyone’s falls somewhere in the “normal” range.
What Is Metabolism?
Metabolism is defined as the series of chemical reactions that burn calories. Those chemical reactions can be further refined into three categories: your resting metabolic rate (RMR), the thermic effect of physical activity (TEPA), and the thermic effect of feeding (TEF).
Resting Metabolic Rate
Here’s some good news. Most of the calorie burning you do takes no extra effort at all. About 60%-75% of the calories you torch through comes from simply keeping your body operating. Like a machine that never turns off, your body is always working, and it always needs fuel, whether you’re running a marathon or sleeping. The organs doing most of that extra work are the heart, brain, lungs, liver, and kidneys, which together make up about 80% of the total calories used every day.
Some people do have a higher RMR than others. Children have especially high calorie needs when at rest compared to adults. On average a child under age 6 at rest burns twice as many calories per pound as an adult. Between ages 6 and 18, your RMR drops by about 25%, and every decade after that your RMR drops another 2% to 3%. That’s mostly because we tend to become less active as we grow older, meaning we tend to lose calorie-burning muscle mass.
Thermic Effect of Physical Activity
The word “thermic” refers to heat. And in this case, we’re talking about the heat generated while moving. That can mean working out, but it can also mean walking to your car or doing the dishes. TEPA accounts for about 15% to 30% of your total calories spent in a day, depending on how active you are. Even shivering and fidgeting count toward this total.
Thermic Effect of Feeding
About 10% of the calories you use up every day come down to TEF. TEF represents all the energy you spend digesting, storing, transporting, and absorbing the food you eat.
Maybe She’s Born with It
There’s some truth to the idea that some people have faster metabolisms than others. Some of us win the gene lottery and have less of a problem keeping off unwanted pounds. The sad reality is that if you’ve ever been overweight, you will have to maintain a stricter diet to avoid gaining again. The reasons why are unclear, but hormone changes during weight loss may be to blame. Appetite suppressants may be helpful in these cases.
Fact and Fiction
The word “metabolism” gets thrown around a lot in dieting circles. Sometimes that advice is useful, but at other times it turns out to be misleading. Should you try a new food? A new workout? More protein? We’re here to help you separate metabolic fact from fantasy. Read on for medical facts verified by health experts that can help you understand the role metabolism plays in weight loss, as well as tips for maintaining a healthy metabolic balance.