How to Read a Scale's Metrics/How to Measure Body-Fat


How do I measure body-fat? I have a scale but there are so many do I read them? Which are important? 

Short Answer:

At-home, bio-impedance scales are not the most accurate devices but can provide a ballpark range of your current numbers, including body-fat. When setting up your scale, you enter your gender, height, and activity level, among other data inputs and the scale provides certain metrics based on your weight, an electrical signal, and the data previously entered. Some key pieces of information are more useful than others in helping define success.

Longer Answer:

Bio-impedance scales work by sending a tiny electrical current through your body, gathering information based on how much the signal is impeded as it flows. This mixed with your vital data inputs produce certain health metrics including Total Weight, Body Mass Index, Body-Fat Percentage, Total Water Count, Basal Metabolic Rate, Muscle Mass, etc. among others depending on the brand and model. All can be helpful but the following three are perhaps the best indicators of success on your journey:

  • Total Weight: While total weight is not the gospel in terms of overall health, it's the easiest and most tangible metric to use when considering success. It is probably the most accurate of the bunch as well and can provide instant feedback throughout your days or weeks.
  • Body-Fat Percentage: Probably the best physical indicator, body-fat percentage is the total amount of fat mass compared to everything else, including muscle/water/bone. This is not to be confused with Body Mass Index (BMI) which is a simple calculation between your height/weight; BMI is an outdated measurement of success as bodybuilders (who have very little fat on them) will fall into the "obese" range due to their higher levels of muscle content. Weight loss is great but fat loss is even better. This is more noticeable through a tape measure/how clothes fit as muscle is smaller and more dense than fat. 
  • Muscle Mass: The opposite of fat mass, your muscle mass is how much skeletal muscle you have relative to your total mass. This is a great indicator of progress as the goal is to develop/maintain as much lean muscle tissue as muscle burns more calories than fatty tissue. It's also important to know when compared to Total Weight, as muscle is more dense than fat and can sometimes prevent the Total Weight number from dropping.

Hand-held devices and calipers are two other common ways to provide measurements but both can fall into the inaccurate category as well. Hand-held devices are identical to scales and calipers can fall prey to user error. There are more accurate ways to determine your metrics including Hydrodensitometry (underwater) tests and Bod-Pods yet both are more expensive and/or difficult to find. Your best bet is using a Dual-Energy X-Ray Absorptiometry (DEXA) scan. This site can find one near you and are sometimes sold in multiple packages, allowing you to monitor your progress throughout the year.

Yours in Health & Friendship,

- The Fit Mother Project  
Customer Success Team

*DISCLAIMER: This information is not intended nor implied to be a substitute for professional medical advice. This FAQ content is for informational purposes only. See our full terms and disclaimer here. Always talk with your healthcare provider about any questions you may have.