The Body Adiposity Index (BAI) of a person simply gauges the content of body fat in percentage form. This can be used together with other measures for body composition such Waist-to-Hip Ratio (WHR) or Body Mass Index (BMI) and Waist-to-Height Ratio (WHtR).
Unfortunately, none of the mentioned methods give a close representation of the body composition and body fat. Because these are all easy and inexpensive relatively, this is preferred for general analysis.
It is not possible to do a precise count of body fat on a living person since fat is found in all of the internal organs of the body. By putting yourself on a weighing scale, this may put some truth to the fact that you have burned some fat.
It may not be so since losing weight may be to loss of muscles or lesser bone density. Conversely, weight gain may signify you are getting fatter or simply you have gained more muscles.
Formula for Body Adiposity Index:
BAI = (Hip Circumference in centimeters / Height in meters ^ 1.5) – 18
Or, another version of the formula which will yield the same
BAI = (Hip Circumference in centimeters / Height in meters x Square Root of Height in meters) – 18