How Accurate are Body Fat Scales?
Have you ever wondered if your actual body fat percentage is anywhere near the number that the digital 
scale reads?
Since the mid-1980’s when bioelectrical impedance analysis technology became more widely used, people have had an easier way to test their body fat. All you have to do is step on a scale that sends a small, harmless electrical current through your body and within a few seconds
you have a digital readout of what your body composition is.
The older versions of this product were widely inaccurate, but within the last 5 years the readings have greatly improved. Although you may still encounter an inaccuracy of +/- 6%, you can improve your results of coming closer to your true body fat percentage by understanding how the bioelectrical impedance analysis actually works.
The electrical current works by estimating how much water is in your body and then from there it calculates how much lean mass you have. After it finds the number of pounds of fat-free body mass you have, it can subtract that amount from your total body weight. What you are left with is your total pounds of body fat, resulting in your body fat percentage.
To get the most accurate reading possible, try to weigh yourself at the same time each day or each week. Keep in mind that the different levels of water you are retaining at varying times throughout the day will affect your body fat reading.
 older posts |
home | newer posts  |
| Controlled Indulgence | | Diet & Weight Loss Blog | | Pomegranates - A Seasonal Fruit |
Posted by: Samantha | Apr 6, 2009 9:13:14 AM
does your scale have an "athlete" setting? i was getting very high readings as well and i know that i am more muscular rather than obese as the scale says! if you change your scale option over to "athlete" it gives a better reading.
Posted by: mike | Mar 28, 2009 11:51:28 AM
same here. I exercise with heavy weights every other day and a cardio light weight routine on off days. I run/walk 11 miles per day. 6'1" 210 pounds and 44 years old. I am pretty muscular but not a body builder by any means. My Taylor body fat scale says I am at 27.2%??? According to the charts I am obese??? I would have guessed I was around 15% or less???? I have tried two different scales of the same model.
Posted by: Adam | Nov 26, 2008 4:23:53 AM
Im having the same problem, my question for you Dan. Is are you taking creatine? My Body Fat Index is 16.6% right now according to my machine, which is very high considering im all cut up. I think it might be because I'm loaded up on creatine and retaining water from it.
Posted by: Dan | Aug 21, 2008 5:19:03 PM
I dont think my scale is accurate in relation to body fat. I am a 41 Yr old male who is athletic. I weigh in at 188. I work out at least 4 times a week, cardio and wieght training and run at least 10 miles per week. My scale says Im at 24.5% body fat (its a new scale). This seems really high to me when the only visiable fat I have is around the mid section and thats not a lot either, I can pich a couple of inches. Legs are muscular, upper body is also lean and I have abs, they are just covered on the bottom with blub. At 170 I would be very thin. How can I have 24.5% body fat when I really only need to lose another 18 or so pounds?
That is 10% of my weight, but at my calculations that would still put me at 14% body fat? This cant be right?
Posted by: RDW | Jun 15, 2008 5:05:33 PM
So the 3% difference that you spoke in one of the responses above. Was that 3% in relation to what the scales will read or 3% in relation to the true body fat percentage?
Posted by: 633 | Apr 28, 2008 5:44:26 AM
Not sure if they are at all accurate. I have weight watchers ones, and my body fat actually goes down after I have a pee according to the scales!
Posted by: Lloyd Shaw Vibra-Train | Apr 7, 2008 3:38:41 AM
I have a number of In-Body bio-impedance body composition machines I use for educational purposes ( 4 Fq ).
What I find them usefull for is the fact they give an idea of internal abdominal body fat ( hidden ). This fat is very dynamic and effects your immediate health unlike static body fat around the arms and legs.
Taking 5% off the body fat store on average = Caliper test.
Posted by: Stephen Cabral | Nov 6, 2007 8:21:34 AM
Hi Elaine,
All things being equal (water weight being the same day-to-day), you are correct.
Posted by: Elaine | Nov 5, 2007 9:05:40 PM
Steve,
Despite the 6% inaccuracy of fat percentage on the scales, you can get at least get a good baseline to start with. From there you can also see if you are consistently losing fat or muscle.
Posted by: Stephen Cabral | Nov 2, 2007 7:26:31 PM
Hi Barbara,
Thank you for the comments.
Body water weight comprises approximately 80% of toal body weight for children, 60% for adults, and 50% for seniors.
If you use skinfold calipers to measure body fat you won't have to worry about water weight effecting your reading. Just let the calipers squeeze the skin for 5 seconds to let any subcutaneous water seep out.
Skinfold calipers are about +/- 3% compared to the digital BIA scales spoken about in this post.
For more information on water weight loss check out my lastest post:
http://blog.nutritiondata.com/dieting_weight_loss_blog/2007/11/are-you-losing-.html
