Weight and Body Fat
How does it work?
While body fat can be measured in many ways, the method used in your scale
is bioelectrical impedance. This indirect method of determining body fat starts when
a safe and very low electrical current is sent through the lower half of the body.
The electrical current flows more quickly through water and muscle than it will
through bone and fat. The scale measures the speed of the current. Based on this
number, the scale estimates body fat using a multi-step, mathematical formula.
Is it accurate?
Measurements of body fat tend to fluctuate a lot more than simple weighing,
and different methods of estimating body fat yield very different results. Just as
different scales give different results, different body fat analyzers can provide
very different body fat estimates. Even with the same scale the numbers will
vary because:
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in body water content. Because body fat analysis is determined by water content
in the body, results can vary considerably from day to day.
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water for the electrical current to flow through. This may result in a higher body
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fluid, it may appear that body fat is lower than it really is.
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weather when skin is moist will yield a different result than if skin is cold and dry.
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trends over time than to use individual daily results.
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an elevated body temperature, diabetes or other health conditions.
What you need to know!
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as expected because total weight loss and total body fat are decreasing at the
same time (for a more detailed explanation, see next section).
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is
normal.
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strength training, in your weight-loss plan.
Why do I lose weight but my body fat percentage doesn’t change much?
Most body fat monitors show body fat as a percentage only. This body fat
monitor shows you not only a percentage but the actual number of body fat
pounds (in fact, this is the measurement you see after your weight is displayed).
Why is that important? When you lose weight, both the numerator (pounds of
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a body fat percentage, the number can be small. For example, a person may weigh
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do not see the percentage change quickly as you are losing weight: monitor the
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lean tissue, include regular physical activity, especially strength training, in your
weight-loss plan.