Obesity is on the rise worldwide, with childhood obesity rates increasing even faster than rates for adults. The World Health Organization (WHO) estimates that adolescent obesity rates have quadrupled since the 1990s. Between 2017 and 2020, the Centers for Disease Control and Prevention (CDC) estimated almost 20 percent of children ages 2 through 19 lived with obesity in the United States.

What’s driving the increasing rates of obesity in kids, and what should parents know about its causes? A common misconception is that childhood obesity comes mostly from poor diet and lifestyle choices, and parents often are given the blame. In reality, childhood obesity is much more complex than bad habits or the oversimplified idea of “calories in, calories out.”

In this article, we’ll explore how a family’s income, their community’s support for healthy lifestyles, and their genes can affect the risk of childhood obesity.

What Is the Primary Cause of Childhood Obesity?

It’s not possible to pin childhood obesity to just one cause, but there are multiple known risk factors. These are related to a child’s diet, the amount of sleep and physical activity they get, their genetics, and their environment.

No matter the cause, obesity is a condition that is diagnosed when a child has a high body weight for their age, height, and sex. Not every child diagnosed with obesity will have other health problems. For some higher-weight children, obesity can affect their physical health, mental health, or self-esteem.

Obesity is also associated with a risk for chronic diseases like type 2 diabetes, hypertension (high blood pressure), high cholesterol, and cardiovascular (heart) disease. Many of these risk factors are hard to change, and it’s important to know that adopting healthy habits may improve your child’s overall health and still not affect their weight. Talk with your child’s primary care team about how you can help make healthy lifestyle changes that will reduce their risk of developing these chronic conditions, regardless of a number on a scale.

1. Genetic Factors

A child’s genetics are passed down from their parents. Genes affect many things about a person, including their appearance and health risks. A child’s genes can contribute to obesity by influencing their metabolism (how the body converts nutrients into energy).

A child whose parents or siblings have been diagnosed with obesity may be more likely to develop childhood obesity, but it’s not a guarantee.

About Epigenetics

Genes are rarely the sole cause of childhood obesity. What’s more influential is epigenetics, or how a child’s environment affects how specific genes work. Hardship from violence, racism, or other stressors can affect how a child’s genes operate, leading to changes in their metabolism.

Another way epigenetics can increase the risk of childhood obesity is through their parents’ health during and before pregnancy. According to Yale Medicine, around 10 percent of pregnant women have gestational diabetes, a type of diabetes that occurs during pregnancy and causes high blood sugar (glucose). Research suggests that gestational diabetes and high weight gain during pregnancy are both epigenetic risk factors for childhood obesity.

2. Family Influence and Lifestyle

Kids learn through observation, and their families influence how they behave inside and outside of the home. A family’s lifestyle influences how much exercise a child gets, what a child eats, when a child eats, and how kids spend their downtime.

However, a family’s lifestyle habits are not always within its control. A family might not have time for exercise, healthy meal planning, and practicing stress management techniques. A household might not be financially stable, and it could be experiencing housing or food insecurity. Our communities can help by providing fresh, whole foods to low-income neighborhoods, clean and safe outdoor spaces to exercise, livable wages with paid time off, and affordable housing options.

Family Lifestyle and Childhood Obesity

The way a family eats and spends free time can lead to weight gain starting in early childhood. It can be challenging to link specific family behaviors to childhood obesity, especially when less observable factors like genetics are at play. These family lifestyle factors can affect the risk for childhood obesity:

• Excessive sedentary screen time
• Eating and snacking habits
• Secondhand smoke in the home
• Not enough exercise
• Traumatic family experiences, which are often out of the family’s control

Research suggests that focusing on the family lifestyle instead of the child’s behaviors may be more effective for childhood obesity prevention. However, these changes can be difficult, and they rely on more than just the family’s willpower. Talk with your primary care team today about how to make lasting healthy lifestyle choices for you and your child. There may be community programs in your area to help support these healthy changes.

Are Parents Responsible for Childhood Obesity?

While parents have some say in their family’s lifestyle, many other factors that influence family lifestyle aren’t so easy to control. For example, even if parents encourage healthy eating and less screen time, childhood obesity can still be affected by socioeconomic status (family income and opportunities), genetics, and the household’s living environment. Community support can make a big difference in families’ ability to make lifestyle changes to improve health.

3. Poor Nutrition and Dietary Factors

Your child’s nutrition may not be the sole cause of childhood obesity, but diet plays an important role. Nutrition isn’t as simple as it seems, and outside influences can affect a child’s eating habits.

High-Calorie Eating and Drinking

When a child eats or drinks more calories than they use for energy, the excess calories are stored as body fat. Talk to your child’s doctor about recommended eating habits based on their age, height, and overall health.

Some foods and drinks have more calories than you might think. Fast food meals typically contain more calories than meals you would cook for your child at home. Many people also underestimate the number of calories in juices and sodas. Research indicates that children who had a fast food meal once a day or who drank two carbonated soft drinks daily had a higher risk of childhood obesity than others.

Low-Nutrient Eating

Many fast and processed foods are high in calories but don’t offer the nutrients your child needs.

Research shows that children who eat fruits or vegetables at least twice a day have a lower risk for childhood obesity. The goal is five servings of fruits and vegetables daily. Talk to your child’s doctor about choosing nutritional meals and snacks.

Excessive Sugar Intake

Research shows that children and adolescents with a high sugar intake are more likely to experience obesity. Some foods naturally contain sugar, like milk and fruit, while others contain sugar added during food processing. Natural sugars are good for most children and should not be discouraged.

Giving your child fewer foods with added sugars can help prevent childhood obesity. Foods with added sugars include:

• Candy
• Baked goods and pastries
• Ice cream
• Sugary cereals
• Condiments like ketchup and barbecue sauce
• Many processed foods that come in packages and boxes

An easy way to check the amount of added sugars in a food is to look at the nutritional label. Under “Total Carbohydrate,” you will see “Total Sugars” and a line that reads “Includes [some amount of] added sugars.” The American Heart Association recommends children have less than 6 teaspoons, or 25 grams, of added sugar in their diets every day.

Another easy way to reduce your child’s sugar intake is to replace sugary beverages, like juices and sodas, with water or milk. MyObesityTeam members have shared other sweet treat alternatives:

• “I do sugar-free popsicles, Jell-O, or fruit like strawberries and blueberries.”
• “I will usually grab a Greek yogurt and add some fruit or granola. Or sugar-free pudding or Jell-O is also good.”
• “Nothing beats a batch of homemade ginger candy. It also takes care of my sweet tooth, and it’s good for the stomach.”

The Role of Processed Foods

Some highly processed foods may contribute to childhood obesity rates. Processed foods have added sugars, flavorings, colors, and other additives. They may have less nutritional value than their whole-food counterparts. Some examples are:

• Frozen and microwaveable meals
• White bread
• Packaged chips and cookies
• Hot dogs and deli meat
• Bottled salad dressings

Processed foods require little preparation, making them convenient options for busy families. Plus, they’re formulated to activate the brain’s reward system, which keeps kids coming back for more. Not sure if a food is processed? Just check the label. Processed foods typically have long ingredient lists full of chemicals you may not recognize.

4. Not Enough Sleep

Kids who don’t get enough sleep or who have poor sleep are at an increased risk of childhood obesity. Studies show that kids who sleep less are also more likely to have poor nutrition. They may consume more calories and be too tired to get as much physical activity as they would otherwise. Studies on adults have also shown that a lack of sleep affects hormones, which can slow the metabolism and increase hunger.

Parents can encourage children to get better sleep by setting a consistent bedtime and reducing screen time. The American Academy of Sleep Medicine says children ages 6 to 12 should be getting nine to 12 hours of sleep, while older children should be getting between eight and 10 hours. Talk to your child’s doctor if they have conditions that affect their sleep, such as sleep apnea, anxiety, or insomnia.

5. Exposure to Marketing Influences

Fast food and snack food companies invest heavily in marketing and advertising geared toward children. Children might see ads on television or billboards. Research shows that even a brief exposure to these advertisements can influence a child’s food choices and contribute to childhood obesity.

6. Lack of Access to Healthy Food

Healthy food may not be readily available to some children and families. Socioeconomic (income and job-related) and environmental factors affect how easy or hard it is to get healthy food. For example, nutrition assistance for low-income families may not be available in some communities.

Food deserts are areas with limited healthy food options. They may not have grocery stores or farmers markets where residents can buy healthy foods like fruits, vegetables, and whole grains. This leaves families in a tough position where their most obtainable and affordable food options are gas stations and fast food restaurants, which can affect a child’s nutrition.

However, the results of a 2023 study showed that living in a food desert was not associated with higher body weight in children.

7. Lack of Access to Safe Exercise

A sedentary lifestyle, or lack of physical activity, can increase a child’s risk of developing childhood obesity. It’s more common these days for children to engage in sedentary behaviors like watching TV and using the internet, which has resulted in kids getting less exercise. This also exposes them to more advertisements that influence their eating habits.

Kids often get time for safe physical activity at school in physical education classes or during recess, but the amount does not meet the American Academy of Pediatrics (AAP) recommendations for exercise. Additionally, getting exercise might not be as realistic at home. Some communities lack recreational facilities, parks, and other safe places for physical activity.

Health Recommendations for Childhood Obesity

Many doctors who treat childhood obesity recommend intensive health behavior and lifestyle treatment (IHBLT) programs to educate and support families’ nutrition and physical activity goals. IHBLT programs are not available for many families, but there are steps you can take.

It’s best to prioritize healthy eating and behaviors over strict weight-loss goals. Helping your child feel good about themselves at any size is important, as is recognizing any step toward improving your family’s lifestyle habits as a positive one.

Focusing on what experts call “positive childhood experiences (PCEs)” can improve your child’s overall health. These include spending quality time together, finding ways to have fun together, and making sure your child feels safe and supported at home and school.

For children whose weight is causing health issues, a comprehensive lifestyle plan can help treat or prevent childhood obesity, but lifestyle therapy has limitations. Genetics, some medications, and other factors aren’t always controllable.

The U.S. Food and Drug Administration (FDA) has now approved several anti-obesity medications for adolescents 12 and older. These include:

• Liraglutide (Saxenda)
• Orlistat (sold as Alli and Xenical)
• Phentermine/Topiramate (Qsymia)
• Semaglutide (Wegovy)
• Setmelanotide (Imcivree)

The AAP recommends starting obesity treatment early, but the right plan depends on each child’s needs. According to AAP guidelines, weight-loss medications can be helpful, but they should be used along with healthy eating, exercise, and behavior changes. These medications work well, but doctors still don’t know much about their long-term effects beyond one year.

Weight-loss surgery, also called metabolic and bariatric surgery, may be an option for teens 13 and older with severe obesity (a body mass index, or BMI, score that is at least 120 percent of the 95th percentile). This is only recommended when other treatments, like lifestyle changes and medication, have not worked.

However, not all families can afford these treatments. Many insurance plans, including Medicaid, do not cover weight-loss medications or surgery.

Talk to Your Doctor

A healthcare provider can work with your child and your family as a whole to treat or prevent childhood obesity. Talk to your child’s pediatrician about your child’s health needs and the best options for childhood obesity management.

Talk With Others Who Understand

MyObesityTeam is the social network for people with obesity and their loved ones. On MyObesityTeam, more than 56,000 members come together to ask questions, give advice, and share their stories with others who understand life with obesity.

Did you have obesity in childhood? Are you wondering about the risk factors of obesity for your child? Share your experience in the comments below, or start a conversation by posting on your Activities page.