EzineArticles.com: BMI or Body Mass Index scales are popular scales used to calculate individual’s body fat index. BMI scales use a technique called Bioelectrical Impedance Analysis, or BIA to measure the fat in a person’s body

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How BMI Scales Work

EzineArticles.com: BMI or Body Mass Index scales are popular scales used to calculate individual’s body fat index. BMI scales use a technique called Bioelectrical Impedance Analysis, or BIA to measure the fat in a person’s body. BIA does this by submitting a small unnoticeable electrical current through the body.

See the rest here:
How BMI Scales Work