Body Fat Percentage

Personally I'm shooting for 1 Kg / month so you are losing weight about 4x what I'm losing. I think really burning 2 pounds of fat a week is unrealistic at your weight. That is roughly 7000 calories! 1000 calories a day of fat burn is basically starvation survival even for a large man. So you are probably losing some combination of fat, lean body mass and water. Hydration could really push up your fat measurements, fat is basically dry and muscle is pretty wet, if you aren't hydrated enough the scale could see it as more fat.

One thing to try is to take your fat measurement at the same time each day, like right after you get up and before you eat or drink. That is just to try and get some consistent hydration while taking the measurement.

Scamd83 wrote: »

Ignore, you said yourself those are not accurate, scales do nothing more than guess your bodyfat. You'd be just as accurate drawing a number out of a hat. Your weight is down so that's good, now start measuring your waist and neck and track those. Without any specialist equipment, that's your best way of tracking fat.

https://en.wikipedia.org/wiki/Body_fat_percentage#Height_and_circumference_methods
That method is known to be inaccurate for body fat percentage. However I completely agree measuring one's waist is a very good way to track progress. It just doesn't tell you much about what percentage of your body is fat. Here is an interesting article: http://time.com/14407/the-hidden-dangers-of-skinny-fat/

Note: I just think the OP has lost the weight too fast for it to all be fat. However I don't have any clue to how much she suffered so I could be completely wrong.

RunRutheeRun wrote: »

Scales don't measure BF accurately. Have you tried measuring waist/hips etc? there are online sites that will guide you through calculating an approx BF, that'll give you a better idea than the scales. To have lost 40 lbs you HAVE to have reduced body fat.
Anyway, bf is not really an issue imo, you should be seeing improvements yourself by now for the better. Keep up the good work

1st: There is no doubt the OP has reduced body fat. You don't lose 40 lbs without doing that. There is doubt about how much fat has been lost. If it is only partly fat and partly water and muscle is completely possible for the percentage of body fat to be the same.

2nd: Measuring waist/hips etc isn't going to be any better than BMI. How actuate it is really depends on how close you fit a model that the equations were built for. Those measurements themselves are useful for tracking but probably lead to a poor estimate of body fat for most people.

3rd: You are complete correct that losing 40 lbs must be showing some awesome improvements.

trigden1991 wrote: »

Bodyfat measurements are inaccurate. Period. Calipers or DEXA scans have the lowest errors. Go by what you see in the mirror!

I really disagree with the calipers being lowest method. I used to use calipers a lot and it is very difficult to even get a consistent measurement let alone an accurate one. It does sound like DEXA scans would be accurate, but I don't have any experience there.

Calipers are a poor method of body fat measurement for the following reasons:
1) Most people try to measure themselves and it is very difficult to get good and consistent measurements.
2) Most calipers are cheap plastic toys not up for the job, a good quality calipers can cost hundreds of USD.
3) Most people don't have the proper training to take caliper measurements correctly.
4) Many equations used were based off of dissection's of bodies over a hundred years ago, I think around the civil war in the US. Anyway the data model probably isn't a close match to most people.
5) Skin folds require many measurement points to be accurate as where people store fat varies widely.
6) Repeated measurements made in slightly different locations, directions and pressures can give different results.

Much of the above applies to diameter measurements, however at least those measurements are more useful for other things like buying smaller clothes!

Scales that use BIA can be reasonably accurate but the following needs to be followed:
1) Standardize on when the measurement is done, for example right have you get up in the morning before eating or drinking and pretty much wearing the same thing. That is so you are at the same hydration level.
2) A reasonable scale won't be cheap for a scale and will have electrodes for both the feet and hands. One of the cheapest I've seen is the Omron Body Composition Monitor Scale, but that runs up to nearly $100 USD.

If you use a cheap scale and don't standardize on measurements you likely won't get good results. Passing current through both the hands and feet are is important because it allows for multiple current paths and measurements.

The big advantages of scales are:
1) They are fast and can be done correctly by a single person.
2) They are really measuring body composition, excluding bone density. Body composition is what is missing from many methods.
3) The results are repeatable with consistent inputs. (i.e. The user is in control of accuracy.)
4) They can make multiple types of measurements at the same time.

Seriously, if measuring impedance was as inaccurate as many people claim, we wouldn't even have simple things like radios that work. The problem isn't the technology it is how it is used.

The OP is asking about why her scale measurements aren't showing changes in her body fat percentage. Most likely is that while she has lost a lot of weight she still have the same percent of body fat. That means fat, lean body mass and water have all been lost. Cardio can be good for burning fat, it can also be good for using up lean body tissue so that might be a factor. The other possibility is inconsistent measurement times and conditions.

I do use a scale and by varying my hydration and weight I can skew the results 0.3% for my body fat and up to 1% on my % muscle mass. Body fat % is more impacted by changes in weight than hydration. It makes sense that women would see more variation than men.