Comparison of ideal body weight equations and published height-weight tables with body mass index tables for healthy adults in the United States.

The purpose of this paper was to compare the ideal body weight (IBW) formulas and published height-weight tables for healthy adults in the United States with the body mass index (BMI) of 22 kg/m2, which is associated with lowest mortality. There are numerous formulas and published height-weight tables available to determine IBW, but there are no published studies comparing the validity of formulas with each other or comparing formulas with BMIs. Data from height-weight tables, weight for specific heights determined by IBW formulas, and weight for BMIs of 20, 22, 25, and 30 kg/m2 at different heights were plotted for both men and women. Slopes based on a range of heights were determined for each formula using relational database software. The value for each slope obtained by linear regression was compared with the BMIs to determine which fit best with BMI of 22 kg/m2. Most height-weight tables and formulas predicted IBWs within the range of BMI of 20-25 kg/m2. However, for shorter heights the formulas were closer to BMI 20 kg/m2 and for taller heights, were closer to BMI 25 kg/m2. Height-weight tables' slopes were closer to the BMI slopes than formula slopes. Robinson's formula appears to be the best equation for calculating desirable/healthy weights in men; however, no formula predicted close to a BMI of 22 kg/m2 for women. Thus, in practice it might be more useful to use BMI ranges instead of IBW formulas for men and women.