Which BMI percentile defines underweight in children?

Which BMI percentile defines underweight in children?

• A. Below 1st percentile
• B. Below 10th percentile
• C. Below 5th percentile
• D. Below 25th percentile

Answer: (C)

In children, BMI is interpreted with age- and sex-specific percentiles. Being underweight is defined as a BMI-for-age below the 5th percentile. This threshold means the child’s BMI is lower than about 95% of peers, signaling potential undernutrition or other health concerns and prompting further evaluation. The other cutoffs aren’t used to define underweight: a BMI below the 1st percentile would indicate more severe underweight, while below the 10th or below the 25th percentile do not meet the standard definition. If a child falls under the 5th percentile, consider assessing growth velocity, nutritional intake, and possible chronic illness.

In children, BMI is interpreted with age- and sex-specific percentiles. Being underweight is defined as a BMI-for-age below the 5th percentile. This threshold means the child’s BMI is lower than about 95% of peers, signaling potential undernutrition or other health concerns and prompting further evaluation. The other cutoffs aren’t used to define underweight: a BMI below the 1st percentile would indicate more severe underweight, while below the 10th or below the 25th percentile do not meet the standard definition. If a child falls under the 5th percentile, consider assessing growth velocity, nutritional intake, and possible chronic illness.