Questions About My BMI

Published: August 09, 2018
Dear TeenHealthFX,

Hi. I am a fifteen year old girl who is going into her sophomore year of high school. I went for my yearly physical appointment today, and it turns out that I’m in the 15th percentile for weight (97 pounds) and the 1st percentile for height (4 feet and 10 inches.) However, my body fat index was in the 58th percentile. I’m confused, because when I calculated my BMI, it said that I was 20.3, which is healthy, but it also said that my body fat percentile was considered obese. What does this mean? I haven’t been allowed to exercise for two years (per doctor’s orders) because of health issues. I’m scared and confused. I thought that if I was in the fifteenth percentile for weight, then I couldn’t possibly be obese. Please help and explain; don’t send me to teenhealthfx links.

Signed: Questions About My BMI

Dear Questions About My BMI,

For our readers who may be unaware, BMI stands for body mass index, and is a formula that doctors use to, “estimate how much body fat a person has based on his or her weight and height.” Being underweight or overweight can cause medical problems, and thus, doctors use the BMI screening tool to determine if someone is considered “healthy” weight or not.

Some important factors to consider regarding weight height and BMI measurement:

  • People grow and develop differently. It’s normal for two teenagers who are the same height and age to have very different weights.
  • Puberty affects BMI. During this time, teenagers will experience faster muscle growth and spurts in height.
  • The “obese” BMI range is a term that doctors use, “for teens whose BMI is equal to or more than the 95th percentile of what's expected for that age and gender. Because there are health risks associated with being obese, this classification helps doctors assess and treat weight problems.”
  • BMI is not the only method to determine how healthy a person is.


TeenHealthFX suggests having a conversation with your doctor who conducted your physical about your weight. You can inquire about your current diet, exercise habits/health issues, and any other lifestyle factors that may contribute to your weight. He/she can help you determine any necessary nutrition and wellness alterations necessary.

If you don't have a doctor and live in northern New Jersey, you can call the Adolescent/Young Adult Center for Health at 973-971-5199 for an appointment with an adolescent medicine specialist or contact your local teen health center or Planned Parenthood. A Planned Parenthood health center is a good option if you have concerns about cost or confidentiality issues. You can also contact your insurance company for a list of in-network providers. 

If you find that your weight is having a negative impact on your mental health and emotional wellbeing, TeenHealthFX suggests reaching out to a trusted adult. You can speak with your parents, school guidance counselor, nurse or teacher. Your trusted adult of choice can help refer you to a certified mental health professional.

FX suggests the following resources for additional information:

Signed: TeenHealthFX