When you get metabolic testing, you walk out with a number, your resting metabolic rate, or RMR. But what does that figure actually mean, and how should it change what you eat? Here is how to read it.
Your RMR is roughly the number of calories your body would burn in a day doing nothing but keeping you alive: breathing, circulating blood, maintaining tissue. For most people it is the largest single piece of their total daily calorie burn, bigger than exercise.
Two people of the same weight can have meaningfully different RMRs. Muscle mass, age, sex, hormones, past dieting, and genetics all influence it. That is exactly why a measured number beats a generic online calculator, which only estimates based on averages.
Once you know your RMR, a dietitian can add your activity level to estimate total daily needs, then set calorie and protein targets for your goal, whether that is fat loss, muscle gain, or maintenance. Retesting over time also shows whether your metabolism is holding steady as you lose weight, which is especially useful during GLP-1 or weight-loss programs.