How common is childhood obesity?

The number of children who have obesity has steadily increased since the 1970s. Recent research showed that almost 1 in 5 children ages 2-19 has obesity.

How do doctors figure out if a person has a healthy weight?

How doctors determine a person’s weight status (whether their weight is healthy for their age, height and gender) depends on their age. Doctors use the Body Mass Index (BMI), or BMI calculator, to determine if a person has a healthy weight. BMI compares a person’s age to their height, weight and sex. You cannot figure out if a person has a healthy weight just by looking at them.

For children, teens and young adults (ages 2-20), doctors determine weight on a growth chart for males or females.

For adults age 21 and over, different BMI measurements include:

  • Underweight – 18.5 and under
  • Healthy weight – 18.5-24.9
  • Overweight – 25-29.9
    Obesity is divided into 3 sections – Class I: 30-34.9, Class II: 35-39.3, Class III: 40 and over.

What are the risk factors for developing childhood overweight or obesity?

  • Maternal and paternal history of obesity
  • Introduction of solid foods before 4 months of age
  • Sleep deprivation (not getting enough sleep) and poor sleep quality
  • Poor eating and physical activity habits
  • Too much screen time (time spent in front of a screen, such as a television, tablet, computer or smart phone)

How do our bodies control weight?

Weight control begins in the first moments of pregnancy. Our bodies control weight in different ways. It is not always a matter of how many calories we take in and how many calories we use. Other ways our bodies control weight include:

  • Genetics
  • Environmental (where we live, work and play)
  • Developmental (how our bodies develop and grow)
  • Behavioral (the habits and actions we have around food, physical activity and wellness)
  • Sleep

What are the effects of childhood overweight and obesity?

There are short-term and long-term effects of childhood overweight and obesity:


  • High blood pressure and high cholesterol, which can lead to heart disease
  • Higher risk of type 2 diabetes (when the body does not use a hormone called insulin properly)
  • Problems with breathing, joints and bones
  • Fatty liver disease (too much fat in the liver)
  • Mood disorders, such as anxiety or depression
  • Low self-esteem
  • Higher risk of bullying from others


  • Higher risk of overweight or obesity as an adult, which can lead to heart disease, type 2 diabetes and many cancers

How can I help my child if they have overweight or obesity?

  • Set a good example with your eating and physical activity habits. Children learn from the people closest to them.
  • Praise your child for positive behaviors around eating and physical activity. Do not focus on your child’s weight.
  • Encourage your child to focus on things they are good at or things they like about themselves.
  • Do not comment on your weight, your child’s weight or the weight of others. Children pick up on how others’ think about weight and physical appearance.
  • Use “person first” language when talking about weight. This means saying a person HAS a certain medical condition, such as overweight or obesity. This is different from describing a person as overweight or obese.

Did you know...?

Physical activity helps maintain a person’s weight more than it helps to lose weight. We should pay close attention to our diet quality. We need foods from all major foods groups to stay healthy. This includes whole grains, lean proteins, fruits, vegetables, healthy fats and very few sweets.

Did you know...?

The effects of being teased about weight can have lifelong effects. Research shows that being teased about weight leads to a higher BMI, overweight and obesity about 15 years later after the first instance of teasing.

Rev. 10/2018