"Body Fat Content" on one of those machines

[arabella]

On hols this week I went on one of those machines that give you
weight (a bit higher than I'd like to think ...)
height (what I told the machine)
systolic bp (96)
diastolic bp (61)  (does this make my bp 61/96, or is it 96/61?  in the well woman thingies it was 74/110 iirc)
heart rate (standing) 90bpm - slightly high I think?
BMI (in the OK range)
body fat content - higher than ideal at 26.6, should be 18-26

are these things accurate and should I be concerned?
are there national variatons (I was in NL)?
what would make body fat high anyway?

those of you who have met me may recall I'm not that chubby*, hence the query
*or maybe I am, and have long been misled by BMI etc.

[hellymedic]

They aren't accurate. We've discussed this before - I'll search in a while. I'd estimate your body fat %age as being towards the lower end of the desirable range for women.
Panic not.

[plum]

I had two of them for a while. always giving wildly differing measurements. The only thing they're useful for really is for showing trends - if a series of measurements is showing a downward trend then at least I'm going in the right direction even if I don't know where the target is.

[border-rider]

are these things accurate

No, not at all.  I consider them worse than useless, because they're totally misleading
 

[border-rider]

I had two of them for a while. always giving wildly differing measurements. The only thing they're useful for really is for showing trends - if a series of measurements is showing a downward trend then at least I'm going in the right direction even if I don't know where the target is.

The  readings will be very dependent on hydration status.  Apart from that, they're just telling you how much conducting cross section your knees and ankles have. Any trends are likely to be secondary to any real change in body fat.

[plum]

I had two of them for a while. always giving wildly differing measurements. The only thing they're useful for really is for showing trends - if a series of measurements is showing a downward trend then at least I'm going in the right direction even if I don't know where the target is.

The  readings will be very dependent on hydration status.  Apart from that, they're just telling you how much conducting cross section your knees and ankles have. Any trends are likely to be secondary to any real change in body fat.

I guess, but I've been measuring and recording mine alongside my weight for a year or so now, and as my weight has dropped, so has the body fat measurement. And fluctuations measured over extended periods such as several weeks holiday when I put on weight have also been reflected in the fat measurement. So whether it's been actually measuring fat levels,  or some other anatomical changes, it is definitely an indication of a real weight loss.

Utterly pointless, because I will have already just weighed myself and seen that I am a pound or whatever lighter, but there you go.

[border-rider]

So whether it's been actually measuring fat levels,  or some other anatomical changes, it is definitely an indication of a real weight loss.

The "body fat" reading will be calculated by the machine based on what it's measured as an electrical impedance, and your weight.  Say that whatever it has directly measured is unchanged - like the size of your knees - then the thing that it flags up as a change in body fat is just you losing weight.

Utterly pointless, because I will have already just weighed myself and seen that I am a pound or whatever lighter, but there you go.

Quite so

[hellymedic]

A tape measure, consistently applied to waist, hips and thighs, would probably yield more useful information in the long term.