Understanding physical development in children is at the heart of my work with families. It’s the basis for knowing what is normal. A child’s good health is indicated by their progressive growth and development.  Learn about your child’s growth patterns, signs of puberty, and more.

I get a number of questions that center around a child’s developmental milestones.

Often, parents want to know: 

“Is my child growing normally?”

“What are the symptoms of a growth spurt?”

“How many inches a year does a child grow?”

“When do girls stop growing?”

In this article, I want to help you understand the physical development of your child, their growth chart, the stages of children’s development, and how growth affects your child’s health.

What is Healthy Growth?

Growth is the process of the body increasing in physical size over time.  Arms and legs lengthen, torso widens and lengthens, and the head grows larger. And, of course, the internal organs, like the brain cells grow, too.

All of these changes happen gradually over the course of childhood and the require energy in the form of food. 

However, there are sensitive periods when the process of child development accelerates.

For instance, baby growth spurts occur in infancy, one of the fastest growing periods in childhood. Secondly, the teen growth spurt is the second fastest time of children’s physical development. 

The Stages of a Child’s Development

During childhood, the stages of growth and development are generally divided into infancy, the toddler and preschool years, childhood, and adolescence. At each of these stages of growth and development, there are certain physical milestones expected, as well as cognitive development, and social skills.

While infancy and adolescence are the fastest periods of growth, during the toddler, preschool, and school-age years growth is at a steady pace.

The Growth Charts: How Healthy Physical Development is Measured

Healthcare providers use growth charts to assess normal progression of growth over time. If your child has a pediatrician or family doctor, at their regular check-ups, your child’s weight and height will be measured and plotted on their growth chart. 

(You can get a copy of the Centers for Disease Control’s growth charts here.)

Growth charts show you the pattern of your child’s growth since birth, including their weight progression, how tall they are at a point in time, and for children under three years, how the head is growing (measure by the head circumference).

For example, on the growth chart, the weight curve can tell you the average female weight based on age, which is the 50th percentile. 

You can do the same with the boy’s growth chart.

Kids grow at various percentiles on the weight and height curves, but each child should track within a predictable channel or percentile, in general, and grow at their own pace.

What is most important to know is that the growth chart is best used as a tracking device, telling you how well your child is growing over time (and alerting you to growth problems if they occur.)

Learn the fundamentals of nourishing the whole child, inside and out.

Belly Fat in School-Age Children 

A client of mine recently asked if his 9 year-old daughter’s belly was normal.

“She’s got a little extra around the middle and I’m a little concerned about it,” said Dad. “She’s active and seems to eat well—and thankfully she’s not worried about it, but I’m a little concerned.”

In school-age girls, the body begins to prepare for the important job of menstruation by laying down body fat in the area of the tummy. You may notice your daughter has a big belly, or is gaining weight in the belly area. This is considered to be a normal transformation for girls to gain weight, particularly in the stomach area. 

Don’t fret too much if you notice your daughter is gaining belly fat before puberty. It’s all part of the growth plan.

In boys, their mid-sections can also get broader in preparation for pubertal growth. 

If you’re concerned about your child’s body size, talk with your doctor or healthcare provider to suss out whether belly fat is a normal part of growth and development, or not.

Puberty Weight Gain and Rapid Growth

For girls, puberty starts around age ten, and the growth rate of their height takes off. You can see this happening on the growth chart. 

When girls get taller, they tend to lose that belly fat they gained earlier, and may thin out over time.

It’s common to notice a body weight redistribution. The addition of fat tissue–to the rear, hips, breasts, backs of arms, and thighs – happens. Your girl is changing into the body of a woman.

Boys experience puberty later than girls, by about two years, making the average start in boys at around age twelve. Boys stop growing around age 16, however, this will be individualized based on genetic inheritance and other environmental factors, like nutrition.

Boys and girls grow and deposit muscle and fat tissue at different rates. Knowing about these normal growth trends can deter harmful interventions (like putting a little girl with a belly on a diet), get you started with additional help if needed (in case of excess unhealthy weight), and most importantly, calm your fears. Supporting your child through this often awkward stage of childhood is key.

When Rapid Physical Growth May Be a Problem

If you notice extra weight gain, more than the normal “pouch” or “filling out” associated with puberty, it may be an indication of excess, unhealthy weight gain. Your child’s pediatrician may say that your child has a high body mass index (BMI). If you hear this, have a conversation with your doctor. Not every child with a high BMI is unhealthy. You know your child best, their habits, and how they are eating. If your child needs more help, discuss an appropriate treatment plan with your doctor. And make sure this conversation is conducted privately, without your child.

Good Growth is Essential to a Child’s Health

When your child is growing well, I am happy and your doctor is happy, too.

Good growth is a hallmark of good physical health. It also means your child’s physical development is on track. 

When your child wavers from his normal channel on the growth chart, like increasing across percentile channels or dropping, it may be a red flag that things may be getting off track.

Growth relies on good nutrition, including enough nutrients and calories. It also depends on good sleep, physical activities, and a healthy lifestyle. You can influence this with lifestyle behaviors and attitudes that promote physical health, inside and out.

More Resources

• We have several workshops, classes and guidebooks to help you successfully raise good eaters and healthy kids!
• Our flagship course, The Nourished Child Blueprint, covers physical growth, psychological development, food, feeding and all the challenges that go with raising and feeding children. 
• Our newsletter, The Munch, offers answers to parent questions, updates on the research about child nutrition and feeding and so much more!
• My latest book, Kids Thrive at Every Size: How to Nourish Your Big, Small, or In-Between Child for a Lifetime of Health and Happiness will help you cultivate the habits and attitudes every child needs to grow up healthy and happy.

Frequently Asked Questions about Physical Development in Children

Below you’ll find some of the questions I am commonly asked about physical development in children.

How Can I Help My Child Lose Belly Fat?

For most children, belly fat will be transitional. That is, it will go away as your child grows taller. 

Make sure your child is getting enough sleep, is physically active each and every day, and eats a nutritious, balanced diet. This will support the natural transition into puberty.

Some people will encourage you to put your child on a diet to lose weight or belly fat. I highly discourage you from taking this approach.

Weight loss diets in children may disturb their eating behaviors, encouraging disordered eating and increasing the risk for an eating disorder. 

What Causes a Child to Have a Big Stomach?

There are other reasons a child may have a larger belly, such as constipation, genetics, an unbalanced diet with too many sweets and treats, or sugary drinks, and a lack of exercise.

My Child Has Sudden Weight Gain

When kids are rapidly gaining weight or appear to have sudden weight gain, you’ll need to assess your child’s routines and habits.

Are they getting enough sleep?

Are they eating regular meals?

Are they snacking too much?

Are they moving their bodies or spending too much time watching TV, playing video games or on their phones?

A change in activity level, sleep routines, and eating patterns can be a good reason for an uptick in weight. And, because the genetic tendencies for size and weight status is strong within families, it may simply be that your child is filling out as expected.

Jill Castle, MS, RD

I like empowering parents to help their children and teens thrive at every size with realistic advice centered on healthful habits around food, feeding, nutrition and health behaviors. As a pediatric dietitian and author, my goal is to share strategies and realistic advice to help you raise a healthy and happy child through my articles and podcast.

This article was originally published in January 2012 | Updated in September 2024