Fact Or Fiction: Muscle Weighs More Than Fat

Most people have heard the phrase that muscle weighs more than fat, but the truth is a little more complicated than that. Technically, a pound of muscle and a pound of fat weigh exactly the same: one pound. But a pound of fat takes up more space than its much denser counterpart, muscle. 

If you are trying to lose weight and are noticing that your pants are fitting looser but the scale hasn't budged, you may be in a situation where you're developing muscle while losing fat at the same time, making your weight stable while your size shifts.

"The difference is that muscle is much more dense than body fat. Therefore, a pound of muscle will take up much less room in your body than a pound of fat," exercise physiologist Katie Heimburger, MS, told WebMD. Simply put, if you're looking at two identically-sized samples of fat and muscle, fat weighs about 80 percent of what muscle weighs (via Banister Nutrition).

Is there a better way to measure fat loss?

If the number on your scale isn't moving, but your clothes are loose, you may want to add another measurement to your weigh-ins. Consider getting a body scan like a DEXA to find out your body composition, use the more old-school style of taking hip and waist measurements with a cloth tape measure, or simply take photos to chart your progress (via Harvard School of Public Health). 

If you notice that you're actually gaining weight despite losing inches, eating right, and exercising regularly, don't panic. "If someone gains 10 pounds of muscle, a lot of times they'll barely notice that on their body, whereas, if you gain five or 10 pounds of fat, you definitely notice that," neuromuscular physiologist Joel Seedman, PhD, told Health

Gaining muscle is a great way to not only improve your overall health but to actually increase the rate at which you lose fat. Heimburger notes that muscle will cause you to burn more calories at rest than fat will (via WebMD).