BMI for Adult & Teenager

BMI, or body mass index, is a measurement of body size. It combines a person's weight and height. The results of a BMI measurement can indicate whether a person is an appropriate weight for their height.

BMI is a screening method that can determine whether a person is underweight, has a healthy weight, is overweight, or is obese. If a person's BMI is outside of the healthy range, their health risks may skyrocket.

Obesity can cause a number of health concerns, including type 2 diabetes, high blood pressure, and cardiovascular problems. Low weight can raise the risk of malnutrition, osteoporosis, and anemia. The doctor will make appropriate recommendations.

BMI does not directly measure body fat and does not take into consideration age, gender, ethnicity, or muscle mass in adults.
It does, however, use standard weight status categories, which can assist clinicians in tracking weight status across populations and identifying potential concerns in individuals.

Adults' BMI

BMI is calculated by measuring a person's height and weight.


  • To determine BMI in metric units, use the following formula: BMI = kg/m2.
  • So, to calculate an adult's BMI, do the following: Divide their weight in kilograms (kg) by their height in meters squared (m2).
  • Because most people measure their height in centimeters (cm), divide your height in centimeters by 100 to get your height in meters.


  • The formula for BMI in imperial units is: BMI = lbs x 703/in2.
  • To put it another way, multiply a person's weight in pounds (lbs) by 703. Then split their height in inches by two (in2).
  • To avoid doing arithmetic, a person can find their BMI using a calculator or a chart.

    BMI graphs

  • BMI of less than 18.5
  • If your BMI is less than 18.5, you are underweight and may need to gain some weight. It is suggested that you seek guidance from your doctor or a dietician.

  • 18.5–24.9 BMI
  • With a BMI of 18.5-24.9, you are at a healthy weight for your height. Maintaining a healthy weight reduces your chances of getting significant health conditions.

  • BMI range of 25–29.9
  • A body mass index (BMI) of 25-29.9 suggests that you are slightly overweight. For health reasons, you may be advised to shed some weight. It is advised that you seek guidance from your doctor or a dietician.

  • BMI greater than 30
  • A BMI of 30 or more implies that you are severely overweight. If you do not lose weight, your health may suffer. It is advised that you seek guidance from your doctor or a dietician.

    BMI in children and adolescents

    BMI values in adults are not related to age and are the same for both sexes.
    However, calculating BMI in children and teenagers is a little different. At different ages, girls and boys develop at different speeds and have varying amounts of body fat. As a result, BMI assessments during childhood and adolescence take age and gender into account.

    Doctors and other health professionals do not categorize children based on appropriate weight ranges for the following reasons:

  • They evolve with each month of life.
  • Body types change at various rates in men and women.
  • As the youngster grows taller, they change.
  • Doctors assess BMI in children and teenagers in the same way that they do in adults, by measuring height and weight. The BMI number and the person's age are then found on a sex-specific BMI-for-age chart. This will show whether or not the child is within a healthy range.

    Final Thoughts

    For most people, BMI is an indicator of body fat percentage. It is used as a screening technique to determine whether an adult's weight is healthy. The advantages of maintaining a healthy weight extend far beyond increased energy and reduced garment sizes. You are more likely to enjoy these quality-of-life characteristics if you lose weight or maintain a healthy weight.