Toddlers come in all sorts of shapes and sizes, so it can be difficult to know if your child is following a healthy path when it comes to their height and weight.
If your child looks bigger or smaller than others of the same age it can be easy to worry that something’s wrong. For us, our super-sized oldest son and super-under-sized youngest son caused many worries. If we had known then what we now know about toddler growth charts, and height and weight percentiles, we’d have worried a lot less.
We’ll save you some of the sleepless nights and needless doctor office visits we went through. Here’s our parent-to-parent guide to toddler growth, the charts, and when you should take them to the doctor.
Key Takeaways
- Toddlers grow at different rates, so comparing your child to others may cause unnecessary worry.
- Growth charts can help track your child’s growth and determine if they are growing at a healthy pace.
- Genetics, nutrition, and medical conditions can affect a child’s growth and size.
- Consult a doctor if you have concerns about your toddler’s growth or sudden changes in their weight.
How Your Child Grows
The average, full-term baby will roughly double their weight in the first four months. After that, growth slows, but only by a little. By the end of the first year, your child’s height and weight will be around three times their birth weight and length.
During the second year, growth slows and the average toddler will gain about 8 pounds and 4 or 5 inches. In the third year, they are down to around 4 pounds and 2 or 3 inches over 12 months, and in the fourth year.
| Age | Size | Girls | Boys |
|---|---|---|---|
| 12 months | Height | 29 inches (74 cm) | 30 inches (75.7 cm) |
| 12 months | Weight | 19 lbs 10 oz (8.9 kg) | 21 lbs 3 oz (9.6 kg) |
| 15 months | Height | 30 ½ inches (77.5 cm) | 31 inches (79.1 cm) |
| 15 months | Weight | 21 lbs 3 oz (9.6 kg) | 22 lbs 11 oz (10.3 kg) |
| 18 months | Height | 31 ¾ inches (80.7 cm) | 32 ½ inches (82.3 cm) |
| 18 months | Weight | 22 lbs 8 oz (10.2 kg) | 24 lbs 1 oz (10.9 kg) |
| 21 months | Height | 33 inches (83.7 cm) | 33 ½ inches (85.1 cm) |
| 21 months | Weight | 24 lbs 1 oz (10.9 kg) | 25 lbs 6oz (11.5 kg) |
| 2 Years | Height | 2 ft 10 inches (86.2 cm) | 2 ft 11 inches (87.7 cm) |
| 2 Years | Weight | 26 lbs 11 oz (12.1 kg) | 28 lbs (12.7 kg) |
| 2 ½ Years | Height | 3 ft (92.1cm) | 3 ft (92.1cm) |
| 2 ½ Years | Weight | 28 lbs 11oz (13 kg) | 30 lbs (13.6 kg) |
| 3 Years | Height | 3 ft 1 inches (94.2 cm) | 3 ft 2 inches (95.3 cm) |
| 3 Years | Weight | 30 lbs 10 oz (13.9 kg) | 31lbs 12oz (14.4 kg) |
| 3 ½ Years | Height | 3 ft 2 inches (97.6 cm) | 3 ft 3 inches (99 cm) |
| 3 ½ Years | Weight | 32 lbs 14 oz (14.9 kg) | 32 lbs 12 oz (15.3 kg) |
| 4 Years | Height | 3 ft 4 inches (101.6 cm) | 3 ft 4 inches (101.6 cm) |
| 4 Years | Weight | 35 lbs 1 oz (15.9 kg) | 35 lbs 15 oz (16.3 kg) |
How Do Growth Chart Percentiles Work?
On growth charts, you will see multiple lines labeled as percentiles. Percentiles show how a baby’s weight and height compares to other children of their age. A child that falls on the 75th percentile is bigger than 75% of children of the same age while 25% of children are larger.
Each line has roughly the same shape but will be on different areas of the chart. Plotting your child’s growth allows you to see if your little one is growing at the expected rate over time, rather than worrying about a specific height or weight measurement.
The height and weight of most babies are tracked on the standard charts, but there are different charts for premature babies and those with certain medical conditions that can affect growth.
The first percentile charts were created in the US in 1977, using data obtained from physicians. Still, concerns were raised that the figures were from predominantly formula-fed, caucasian, middle-class families.
In 2000 the charts were updated with more extensive data from a much more comprehensive range of children (1). As a result, the charts are more representative of all US babies.
What If My Toddler Is Bigger or Smaller?
There are a variety of reasons why your toddler may be bigger or smaller than their peers (2).
Some common reasons for this are:
Genetics
Look back a couple of generations to see if your child may have inherited their taller or shorter than average status.
Our youngest son barely hit the fifth percentile, even though we are taller than average. However, a quick look at the family tree revealed that his paternal grandfather was just 4” 10’ in adulthood and it turns out our son inherited his stature.
Improper Nutrition
Children who do not have enough food, or do not have enough food with appropriate nutritional value may fail to grow at the same rate as their peers. Children without enough food will not have the calories or nutrition their body needs to grow, resulting in a smaller child.
Growth Hormone Issues
Growth is moderated by hormones and for several reasons a child may have too much or too little growth hormone. As you might expect, too much growth hormone would cause a child to grow faster than others and too little will prevent adequate growth.
Thyroid Disorders
The chemicals released by the thyroid moderate bone growth. So, if a child has hypothyroidism their body doesn’t produce enough and they do not grow at the expected pace.
Systemic Illnesses
Children living with chronic health conditions or long-term illnesses may fail to grow at the average rate. This can be because the illness directly affects growth, because nutrition is “burned up” fighting an illness, or because a child feels too unwell to take in enough calories.
Failure to Thrive
Rather than a specific illness or condition, failure to thrive is a general term for a child who doesn’t grow at the expected rate (3). The causes of failure to thrive vary, and sometimes no particular cause is ever identified.
Is It Normal for Toddlers to Lose Weight?
Toddlers may lose weight when they are sick, but regain that weight in the following weeks and months (4). They might also lose weight in comparison to their height, which is a reflection of the fact they are more active.
If your toddler suddenly loses weight when they haven’t been sick, loses an excessive amount of weight when they are ill, doesn’t appear to be regaining the weight, or seems to be getting taller but no heavier, it’s worth visiting your doctor to check in.
When Should I Worry About My Child’s Weight?
There’s no need to worry about where your child starts on the growth chart. If they are healthy, the fact they are in the 5th or 95th percentile is unimportant.
What should raise concerns is if your child starts at the 95th percentile, happily hangs around that point for a couple of years, and suddenly drops to the 75th. Or, if your 5th percentile child suddenly jumps up to the 25th.
If this happens, or your child gains or loses a significant amount of weight in a very short period of time, speak with your doctor.
How Can I Get My Toddler to Lose Weight?
If your toddler is following their previous healthy growth curve, they do not need to lose weight. Some doctors use BMI, Body Mass Index to assess a toddler’s weight in relation to their height, but current research suggests it is an unreliable measure for children under nine (5).
Dump the Thought of Diets
Putting your toddler on a diet, telling them they have to lose weight or labelling foods as good, bad, or naughty can lead to a lifetime of psychological issues, weight problems, and even eating disorders.
Rather than forbidding certain foods or telling them they can’t eat “bad” foods, think instead in terms of healthy habits and unhealthy habits for the entire family. Instead of focusing on losing weight, allow your child to keep their weight the same, as they grow taller.
Encourage Healthy Family Habits
Provide a wide variety of healthy foods and snacks, but don’t forbid any particular food, and listen to your child when they say they’ve had enough at a meal time. Encourage the entire family to eat together and model healthy eating habits for your child.
Another excellent way to help your child embrace a change of eating habits is to get them involved in planning meals and shopping. When your little one feels they have input to their food choices and an element of control, you are less likely to find yourself arguing with a tiny tyrant.
Take It Slowly
However, don’t try to change everything at once. Just like adults, toddlers have a certain level of comfort in knowing things are the same and a sudden, complete change of eating habits can cause anxiety, ultimately being counter-productive.
Get Active
Ensure your little one has plenty of opportunities to be active, but don’t worry about making them exercise in a formal way or participate in sports unless they see other people doing it and want to join in.
Instead, walk wherever you can, and look for ways to keep them active when you’re indoors. Things such as setting up an obstacle course can be fun to do, doesn’t require fees or equipment, and can be modified as your child grows.
Try Not to Worry
Easier said than done, I know. But try the best you can not to worry about your toddler’s weight. Unless they are significantly overweight for their height, there is likely nothing to be worried about.
However, if you do have any concerns, speak to your doctor before changing anything. It’s likely there’s nothing wrong with your toddler’s growth, but if there is an issue, it’s best to deal with it under medical supervision, after ruling out any specific, medical, treatable causes.
