theyre right BMI doesnt take into consideration things like muscle weight or body fat percentage, its very outdated
It's still a good range to see if you're in a bad situation. Unless you're some literal bodybuilder, it'll still give you a decent parameter on how fat you are >_>
What other measures of body fat are available? Some research suggests that other measures of body fat, such as skinfold thicknesses, bioelectrical impedance, underwater weighing, and dual energy x-ray absorption, may be more accurate than BMI. The waist circumference (sometimes divided by height) is also a simple measure of fat distribution. Although these measures may provide a better indication of an individuals body fatness and risk of obesity-related health problems, they can be expensive, intrusive, not widely available, or difficult to standardize across observers or machines. Some of these measures are considered inappropriate for routine clinical practice because they are technically demanding and rely on more complex technologies. In addition, most of our knowledge concerning obesity-related health risks is based on the association of BMI to various outcomes. There are few reference standards for body fatness based on the above-mentioned measures, and without established risk categories, it is difficult to determine if the body fatness of an individual is low, moderate, or high. Consequently, other measures of body fat are not recommended for routine practice. What should we conclude about BMI? BMI is a reasonable indicator of body fat for both adults and children. Because BMI does not measure body fat directly, it should not be used as a diagnostic tool. Instead, BMI should be used as a measure to track weight status in populations and as a screening tool to identify potential weight problems in individuals.