The human body is an amazing thing. Physiologically, there are so many things that happen in unison that keep us alive. Muscles, bones, and fat are three major components of the body. We need all three to survive, including fat. Having too much or too little of any of these things can lead to a multitude of health issues. So how can you find out how much you have?
First, let's look at body composition. Body composition is essentially how much muscle, bone, fat, and water compose the body. For body composition, it is more of a comparison of fat free mass, or lean mass, to fat mass. Everyone's body composition is different. For example, women tend to have a higher percent of fat than men of the same age for a number of reasons (i.e. childbearing, hormone regulation). As you age, body composition changes as well (i.e. muscle atrophy).
Body mass is different from body composition. Instead of looking at lean mass vs fat mass, it is more of a ratio. Body mass index (BMI) is a comparison of total body weight to height; it does not look at the composition of the body but the sum of all its components. Many healthcare professionals and fitness experts use BMI to find a correlation for body fat. This height to weight ratio gives an estimate for percent body fat. Once found, it can be compared to a chart which takes into consideration your age and gender to see if it is a “healthy” percent. This can be a great tool for much of the general population. But because BMI isn't considering how much of the total body weight is fat and how much is muscle, etc., it is not always reliable. Take a professional body builder, for example: lots of muscle, very little body fat. According to their BMI, they can sometimes fall under the “obese” category simply because of their height to weight ratio.
One common misconception I’ve heard is that muscle weighs more than fat. This isn’t entirely true; a pound is a pound no matter what. What this is referring to is actually the difference in density. Muscle is more dense than fat is. Simply put, a pound of muscle takes up less space in the body than a pound of fat does. This is important to understand when you look at total body weight.
When you get on a scale, it tells you a total body weight. If you are eating correctly and exercising to lose weight, try not to rely on the numbers on the scale for progress. You could be losing body fat and gaining muscle but weigh exactly the same. Take a look at yourself in the mirror- how are your clothes fitting? How are you feeling? These are better for determining progress than a number on the scale. This can happen in reverse too; you can lose muscle and gain fat, essentially weighing the same but physically look “bigger.”
If you are interested in finding out your body composition, contact your doctor or a facility that conducts body composition testing. Remember, if you feel better, that is the most important thing! Don’t compare your progress to anyone else or a quantitative number because it isn’t always reliable.
Blog post by Nikki Courtney.