Many height and weight tables are not accurate, according to HealthStatus. Calculations that take into account factors other than height and weight, such as age and frame size, are more accurate. Many health professionals rely on BMI (body mass index) as a reliable way to determine whether a person is underweight or overweight, but since BMI is calculated based on height and weight, some professionals consider it unreliable, according to WebMD.
Children and teenagers cannot rely on weight tables or ranges to determine overall health, according to the CDC. Since young people grow from one month to the next, static charts provide insufficient data to determine whether a child is overweight or obese.