We often blame ‘slow metabolism’ for our inability to keep our weight under control. But what is metabolism, exactly? And, is there anything we can do to change our metabolic rate?
Metabolism refers to all the chemical processes that take place in the body in order to sustain life – processes that allow you to breathe, pump blood, keep your brain functioning and extract energy from your food. Your basal metabolic rate refers to the number of calories your body uses each day, at rest, just to keep all your vital organs functioning.
The metabolic rate is directly related to your body composition. Every pound of body fat you have burns only about 2 calories a day. But the rest of you – your lean body mass – burns about 14 calories per pound each day. A big portion of your lean body mass is made up of muscle, so one of the best things you can do to boost your metabolic rate is to build up muscle through strength training. And, make sure to take in adequate protein from the diet, which helps to build and maintain lean muscle, too.
Here are the facts surround five myths about metabolism:
Myth: Aging slows your metabolism.
Truth: People do tend to put on weight as they get older – but it’s typically because they tend to exercise less, or less vigorously, than they used to – and that means fewer calories burned per day. As a result, loss of muscle mass can occur which reduces the body’s lean body mass – which results in a slower metabolic rate. Cardiovascular exercise to burn calories and strength training to preserve or build up muscle are great defenses against age-related weight gain.
Myth: You’re stuck with the metabolism you have and you can’t change it.
Truth: While it may appear that there are people who eat all the time and never seem to gain, chances are they make healthy, relatively low calorie selections naturally. Many of these “lucky” people also burn more calories simply because they move more - they might fidget more, or get up from their desks frequently during the day to stretch, or walk down the hall to talk to a colleague instead of e-mailing. So, once you’ve made the commitment to boost your metabolism by building more muscle, use those muscles more by moving around frequently throughout the day.
Myth: You burn more calories digesting ice-cold foods and beverages than foods that are room temperature or warmer.
Truth: In a laboratory, very slight increases in calorie burn have been measured in people who drink very cold beverages. But the change is too small (amounting to about 10 more calories burned per day) to have any meaningful impact on weight loss.
Myth: If you cut calories, your metabolic rate will slow down, so what’s the point?
Truth: It is true that your metabolic rate can slow a bit when you cut calories – your body’s natural inclination is to try to conserve calories as best it can. But, these decreases are relatively small, and if you become more active as you lose weight, you can offset these small changes. With a combination of diet AND exercise, you can help to preserve the rate at which your body burns calories.
Myth: If you stop eating at night, when your metabolism is slower, you’ll lose more weight.
Truth: When people lose weight because they stop eating after a certain time of day, it’s only because they’ve cut their overall calorie consumption - not because they are eating their calories earlier in the day. Consuming all your calories before the sun goes down won’t speed up your weight loss unless you also eat fewer calories than you need.
Susan Bowerman is a consultant to Herbalife.