Healthy Height To Weight Ratios

Whether using height and weight charts or mathematically calculating body mass index, identifying health risk based on height and weight is a quick and simple method for health care providers to categorize patients. But for many people, height and weight calculations do not accurately reflect body fat or health status.

Height, Weight and Health

According to Columbia University social science researcher Amanda M. Czerniawski, the advent of the penny weight scale in the late 19th century marked the beginning of America's obsession with body weight, enabling us to quantify a previously subjective concept of fitness. Around the same time, the genesis of the life insurance industry prompted the development of height and weight tables to categorize health risk at a time in history when being underweight was of greater concern to medical practitioners than being overweight. It was not until the 1940s, when food rationing during World War II was at its zenith, that obesity became unfashionable and height and weight charts morphed from being an insurance trade tool to a standard of acceptable health.

Stillman Height-to-Weight Ratio

In the 1960s, diet guru Dr. Irwin Stillman developed a height-to-weight ratio formula for determining a realistic healthy weight for your height. For average non-athletic men, the formula allots 110 pounds for the first five feet in height and 5.5 pounds for each additional inch. For average women, the formula allots 100 pounds for the first five feet in height and five pounds for each additional inch. While the Stillman formula has been displaced in the health care arena with body mass index, or BMI, it still is used by many distance runners.

Body Mass Index

Body mass index produces a ratio based on height and weight, comparing body weight in kilograms to height in centimeters squared. Because BMI is easy to calculate, it often is used by health care providers to assess health risk. Using the BMI formula, a score less than 18.5 is considered underweight, 18.6 to 24.9 normal, 25 to 29.9 overweight and over 30 is obese. However, critics of BMI note that it does not necessarily correlate with body fat, and is not an accurate tool for assessing growing children, elderly sedentary individuals and muscular athletes. BMI does not allow for extra lean muscle mass characteristic of athletic individuals, and a physically fit person with very low body fat can appear to be overweight or even obese using BMI.

Body Fat Percentage

The best way to determine whether you are at a healthy weight is to calculate your body fat percentage. Bioelectrical impedance sends a mild electrical current through your body on the premise that muscle, which contains water, is a good electrical conductor while fat is not. But even these devices factor in height and weight, and results can vary depending on hydration levels. For the most accurate measure of body fat, ask a trained professional to assess you using a skinfold caliper or hydrostatic weighing. For good health, Montana State University adjunct professor of sports nutrition, Patti Steinmuller, MS, RD, LN, recommends average women strive for 20 to 25 percent body fat, and average men 15 to 20 percent.