What is the Body Mass Index?

4. Limitations of the Body Mass Index

Some experts criticize the blanket use of the body mass index as the only measure of body weight because it has certain limitations. For example, a BMI measurement cannot discriminate between whether a person's weight is because of fat or muscle. For this reason, very muscular individuals or athletes may be classed as overweight or even obese despite having no increased risk of disease. Another criticism of BMI is that it fails to take a person's body shape into account when arriving at a measurement. For instance, a person with a small body frame could be carrying considerably more body fat than a person with a larger frame but of the same height and weight. BMI cannot be used to accurately assess the weight of pregnant women.

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