Accuracy of BF% on Scales?

NakAttack

We recently purchased an expensive scale that gives you your weight along with BF%, water %, etc. I am starting to wonder just how accurate it is. I have lost three pounds since we bought the scale three weeks ago along with 6.5 inches from my belly thighs and arms. Common sense would tell me that I would see some changes in my BF% but not much. I am at 31.6% and started at 32.5%. Is this normal or should it be moving more?

I am also starting to wonder about the accuracy of the device. Thoughts?

Kai81109

not really accurate at all the most accurate way would be hydrodensitometry testing.

BarackMeLikeAHurricane

Terrible. Last time I used any sort of bio electrical impedance device it said my fat *kitten* was 10.8% body fat lol. Go to amazon and buy calipers for like $10 or less. It's not 100% accurate, but other than bod pod or DEXA (which are both expensive) it's your best bet for at home estimations.

yarwell

they aren't too bad and are at least accessible.

32.5 to 31.6% is a good improvement


You lost 3 lbs - let's say 180 starting at 32.5% fat then fat free mass (FFM) = 121.5 lbs

Now 177 lbs at 31.6% fat FFM = 121.0 lbs

suggesting you lost 3 lbs of weight of which 0.5 lbs was FFM and 2.5 lbs was fat. That's good.

kazzsjourney

They are generally innacurate but allow you to see a trend. They are also affected by how hydrated you are.

gracielynn1011

Mine was a total waist of money! I have two scales, one regular old dial scale and then the fancy smancy body fat reading, accurate to .01 lbs electronic scale. The electronic always reads 4 lbs heavier each week. And it varies the body fat % each week. One week it said 31%, the next it said 46%.

6spdeg

they are crap not even close.. but you are supposed to i believe watch over a 30day period and take the average... but still inaccurate in all of my experiences.

karint74

I use mine to track trends only. I *know* it reads really high--it tells me I'm 31% bf at my current weight (see my profile picture). I don't think so! Also, per suggestion of one of my MFP friends, I changed the age setting to see if it would affect the bf% reading. When I dropped my age setting to 10 years old (the minimum setting), I instantly lost 0.9 bf percentage points! I guess this is supposed to account for the increased abdominal fat that comes with age that the scale is mysteriously unable to detect. Whatever.

It's good to track trends over time. Time as in months. Since I started MFP at the end of August 2012 I'm down 10 bf% points. That is information that is motivating!

aFootballLife25

Not accurate in the least bit. Even calipers are WAY more accurate. I'd try to return the scale.

RobynLB83

BF scales are not accurate at all. Try calipers (a little tricky, but at least you can track changes), or just gauge your results by your measuring tape measurements.

NakAttack

Thanks everyone for the responses! I will try and find some caliphers on Amazon. My husband is a health nut so we probably have some lying around the house somewhere. Thanks!