The average height for a 9-year-old
1. What is the average height for 9-year-old boys and girls?
1.1. The average height for a 9-year-old boy
A 9-year-old boy typically grows to a height of 133.3 cm.
1.2. The average height for an 11-year-old girl
Meanwhile, the typical average height for a 9-year-old girl is 132.5 cm.
2. How to know if a 9-year-old is tall or short?
The table below shows the average height growth month-by-month for boys and girls between the ages of 9 and 10.
Growth rate of height by month at 9 years of age in boys and girls (WHO)
➤ What is considered tall for a 9-year-old?
The average height of boys and girls will rise by 3 to 5 cm between the ages of 9 and 10.
A 9-year-old boy's height exceeding 144.6 cm and a 9-year-old girl's height above 144.7 cm may indicate early or premature signs of puberty.
➤ What is considered short for a 9-year-old?
If a 9-year-old boy is 120.5 cm shorter and a 9-year-old girl is 120.3 cm shorter, your kids can be considered short.
3. Reasons why children are slow to grow taller than their age
When a kid seems much smaller than most of their classmates, parents usually become very anxious and worried. So what are some reasons causing children's height to slow down?
3.1. Children who have a family history of low height
Given that height is usually inherited from parents, if one parent is short, there is a high chance that their kid will also be shorter than their peers.
3.2. Children with systemic diseases, bone diseases, or endocrine disorders
These systemic diseases include persistent undernourishment, digestive system illnesses, renal ailments, heart problems, lung diseases, diabetes, or chronic illnesses. It is challenging for kids to accomplish the proper height growth for the appropriate age if they have a history of rickets.
3.3. Children with unhealthy lifestyles
Most of the time, an unhealthy lifestyle - rather than a disease - is to blame for children's delayed growth in height. This lifestyle includes poor diet, lack of exercise, and daily overindulgence.
3.4. Children with poor eating habits
Children who frequently consume processed meals, spicy foods, high-sugar foods, carbonated soft drinks, fatty foods, etc. will develop more slowly than children at the same age. This is because their daily diet does not provide the bones with enough nutrition.
However, in some other cases, overeating in children can lead to the risk of obesity and thus, stunt their growth at an early age.
3.5. Children are lazy to exercise
One of the main factors influencing height growth is movement. Children who are sedentary cannot catch up with age-related development. Children who aren’t active are more prone to gain weight, experience bone issues, or develop early joint closure. All of this could be the reason behind their slow increase in height.
3.6. Children stay up late, and wake up late
Growth hormone levels are at their highest while you sleep. Hence, it could be challenging for this process to take place if your children don’t go to bed on time. According to studies, kids who stay up late tend to grow taller more slowly and are 5–10 cm shorter than their classmates .
4. How to help your kids grow taller at 9?
Even if your child is not genetically tall, they can still grow to be as tall as their classmates. Here are some actions you can take to help your child grow taller.
4.1. Consume a nutritious diet
A diet should contain all four categories of essential nutrients on a regular basis. All of the body's tissues, muscles, cartilage, bones, and organs need protein to grow, hence protein is a must-have nutrient. Next, healthy fats should be consumed since they provide the brain and neurological system with vital nourishment. In addition to using carbs as its main energy source, the body also utilizes them to build new tissues and cells. Not to mention, vitamins and minerals are necessary for the normal growth and function of every organ in the body.
4.2. Take enough vitamin D
Dietary and lifestyle changes won't improve height unless your kids get enough vitamin D. Vitamin D helps the body absorb calcium, which is necessary for the development of bones and muscles. Being overweight and experiencing stunted development is said to be related to vitamin D insufficiency. 
Foods strong in vitamin D, such as mushrooms, fatty fish, orange juice, beef liver, egg yolk, fortified cereals, milk, and other dairy products, should be consumed often. Sunlight exposure is also advised for vitamin D synthesis since it aids in converting inactive vitamin D levels into active ones. However, your kids should only spend 5 to 10 minutes in the sun if they don’t want to get sunburned.
4.3. Use dietary supplements for height increase
In some cases, taking supplements is advised because they are packed with nutrients that support height and natural growth rate. Using these supplements can be more beneficial if your kids' growth plates are still developing. The products may not all be efficient for people of all ages, so always check with your doctor before using anything.
4.4. Stay hydrated
Cells serve as the main organs for facilitating vitamin and mineral absorption. Drinking water enhances the functionality of these cells and hastens the absorption process. It also lessens toxic compounds in the body, which speeds up metabolism. If your kids take part in any sports, they should drink extra to keep hydrated.
Kids should be active for at least 60 minutes per day. You should encourage them to try many different sports without exerting pressure on them, and try to give them the freedom to pursue their own interests.
4.6. Get proper sleep
Your kids should get enough sleep from 8 to 10 hours every night. Any child who wants to increase their height and properly develop their body has to get enough sleep. That is because their body heals and grows while they're asleep.
4.7. Improve body posture
If your kids constantly slouch or hunch, these curves may change to match your new posture which can make them appear shorter than they actually are.
4.8. Dress properly
Darker shades of clothing, such as deep blue, black, and red, should be used if your kids want to appear taller and slimmer. Wearing clothing with vertical stripes also can make them look taller than when wearing clothing with horizontal patterns.
Children still have plenty of opportunities to grow taller at the age of 9. Instead of obsessing over whether or not their children are of average height, parents should encourage them to live a healthy lifestyle. If you have any further worries about your children's growth rate, you should talk to a health specialist about it.
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