T Nation

Tricking a Body Fat Scale


I have a quick question for those in the know. A buddy of mine is in a body fat loss contest at work(largest % of bodyfat lost wins) and they are using a tanita scale to measure the % fat loss for everyone.

I have always heard drinking large amounts of water would/could throw the scale off, but Im not sure if this is true.

Are these scales reliable and aren't there numerous ways to "trick" these scales?


Tell him to get off his lazy ass and get lean. There are plenty of articles here to assist him.


What I've always heard about these scales is that while they aren't very accurate in the sense of measuring what your bodyfat really IS, they are excellently consistent and can be used to track changes in bodyfat, provided you're at the same level of hydration.

But, yes, for me even one meal in my stomach can increase my bf measurement by about 2%, but as long as I measure in the morning it's been surprisingly helpful.


I heard something about someone taking his bf% with one of those, then eating a lot of food, drinking a lot of water, and actually decreasing his bf% according to the scale.

I don't remember what he ate, or how much water he drank to do it though.


If you grab your ankles it'll just about halve your bf%.


I have one. It's true that if you drink a ton of water it will drop the reading by several percent. I'm not sure about the food because I normally don't eat large meals without large quanities of liquid.


They do 2 measurements 1 in the morning and 1 in the afternoon and take the average to factor in fluctuations.

Hypothetically speaking, if you were to do say a fleet 3 kit to cleanse you out would that have any effect on the body fat measurement in itself?


The tanita's a piece of shit. Not only is its actual detrmination of bodyfat wildly innacurate, but it fails to differentiate betwen muscle, fat, and water. When I had one, if I chugged a lot of water quickly after getting a reading, they bodyfat on the 2nd reading always went up. So, that won't work. It's a stupid contest. If anything, they should test bodyfat an accurate way.


Never did for me. It raised it. Maybe I had a faulty scale. But really, I just think they're crap


For some reason my tanita reads a super low bodyfat if I weigh myself after a hard workout


I have one and I like it, yet I question its accuracy. There are wild variations in its bf readings throughout the day. IT seems to me that if you are dehydrated it shows a lower bf %, also drinking water just before the weighing raises it. So you friend should go on the velocity diet for a month, then before his final weigh in he needs to get out the trash bag sprint suit, or the sauna workout if he has access to one.


They may not be "excellently consistent", but if you use the scale at the same time of day and when you are similarly hydrated, they will show you a trend over time of either decreasing or increasing your percent bodyfat.


A high sodium meal beforehand will cause a lower reading on many bodyfat scales, I don't know specifically about the Tanita but I would imagine that holds as well.


I tried a similar scale (wasn't tanita but same idea) and I registered 4% less bodyfat after eating a huge plateful of BBQ (pork & beans) and dropping deuce shortly thereafter. This is the reason I don't think they are accurate but I wasn't sure if it was an abnomaly or the norm.