Jan 9, 2017, 8:15:48 AM CST Jan 24, 2023, 11:58:39 AM CST

Should I worry about my child's BMI? Body mass index explained

BMI measurements can cause a lot of confusion for parents. Learn what BMI means for kids.

doctor weighting and measuring little girl doctor weighting and measuring little girl

Does your doctor say your child's body mass index (BMI) puts them in the overweight category, but you think they look healthy? BMI measurements can cause a lot of frustration and confusion for parents.

"Developing healthy habits at an early age is crucial as children grow and develop. Children with a BMI over the 85th percentile have a greater likelihood to have obesity as an adult, placing them at risk for future health complications.

What does BMI mean?

It is hard to tell whether a child is overweight or obese just by looking at them. Body mass index, or BMI, is a ratio of height and weight that is a reliable way to estimate body fat in most children and teens.

Since the normal body fat of a child changes as he or she ages, your child's status is found using categories that are age- and sex-specific. See the BMI calculator for children and teens.

What are the risks of an elevated BMI?

Having an elevated BMI can increase the risk of developing type 2 diabetes, heart disease and high blood pressure. While culturally we may be okay with our child's weight, we must consider the implications of their weight on their future health.

After a child's BMI is calculated, it is measured against other children of the same sex and age to get a general picture of how their BMI compares. If your child's weight is in the 85th percentile, their BMI is higher than 85% of children of their same sex and age.

BMI and weight categories

A child's BMI percentile will place them in one of the following categories:

  • Underweight
    • Percentile Range: Less than the 5th percentile
  • Healthy weight
    • Percentile Range: 5th percentile to less than the 85th percentile
  • Overweight
    • Percentile Range: 85th to less than the 95th percentile
  • Obese
    • Percentile Range: Equal to or greater than the 95th percentile
  • Severe Obesity
    • Percentile Range: Equal to or greater than the 120th percentile

The most important thing to know about the BMI is that it is a screening tool to identify potential weight problems, not a diagnosis. To diagnose a child as overweight or obese, your physician will take many other health factors into account. If your child is far from a healthy weight, be patient and focus on making small changes towards a healthier lifestyle as opposed to concentrating solely on the scale. It is best to track it over time, because as your child grows, their body fat will change along with their BMI.

It is best to avoid using the terms overweight and obese with children and focus on being at a healthy weight. Learn more tips about speaking to your child about weight. If you are concerned about how to help your child eat healthy, speak to your physician about resources and appropriate strategies.

Learn more

Interested in learning more about healthier habits for your family? Read more about pediatric weight management programs that include Get Up & Go, COACH, bariatrics and nutrition clinics.

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bariatrics, behavior, body image, BMI, diet, eating disorder, mental health, nutrition, physician advice, obesity

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