Are Scales that Measure Body Fat Accurate?

When you step on a scale to weigh yourself, the number the scale spits back at you reflects the weight of both lean body mass - such as muscle '" as well as body fat. Hydration or the amount of water in your system also influences this number. This makes if difficult to know how much progress you're making with a diet or exercise program. You may be gaining lean body mass and losing fat which would keep your weight the same '" despite a drop in body fat. The good news? There are scales that measure body fat that you can purchase to measure your body fat percentage at home. Are these body fat scales really accurate?

How Do Scales That Measure Body Fat Work?

A scale that measures body fat looks very similar to a traditional scale. You step on a platform and the scale sends a weak electrical current into your feet which moves up your body and returns down the opposite leg to the other foot. The current moves more rapidly through muscle than it does through fat tissue or bone, so it reaches the opposite foot more quickly when there's a higher muscle to fat ratio. The body fat scale then spits out a number that reflects a measurement of your body fat percentage.

How Accurate is the Scale at Measuring Fat Percentage?

Not completely accurate. Several factors can alter the results. One is how much water is your system prior to weighing. If you weigh first thing in the morning when you're dehydrated, your body fat percentage will be elevated by a few points '" and you may think you're chubbier than you actually are. On the other hand, if you just drank a jug of water, your body fat may be falsely depressed. There are other factors that can throw off the results - even something as minor as having dirty or cold feet.

Body Fat Scales: Are They Worth It?

Scales that measure body fat aren't very accurate for measuring absolute body fat percentages because too many factors can alter the results. On the other hand, if you use them to measure body fat percentage at the same time every day when you've taken in about the same amount of water, the results will be consistent. This also assumes that you've cleaned your feet well and your feet are about the same temperature each time.

By weighing every day and writing down the numbers you can see whether your body fat percentage is increasing or decreasing '" which allows you to alter your eating and exercise habits. Keep in mind that scales that measure body fat can be expensive and they may not be worth it for everyone. The bottom line? Body fat scales can still be a helpful tool for monitoring progress despite their inaccuracies.

References:

Shop Smart Magazine. March 2010. page 59