"Bizarrely, it was a tape measure that brought it home to me, " he laughs.

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And busy doctors may resort to the scale rather than take the time to use a tape measure correctly, Michos says.

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Other important measurement tools include the ruler, the protractor, the tape measure.

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Recently, he took Niel on a walking tour of Home Depot, where the toddler studied different kinds of hammers and learned how to use a tape measure.

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Conversely, if a tape measure reveals a decrease in waist circumference, you can see the benefit and know you're improving your health, which can also motivate you to continue an exercise and diet plan.

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Because the 3D scanner does not compress the skin like a tape measure does, and the scanner also measures the small of the back, it produces waist measurements around 1.9cm larger than a tape measure.

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