Ensuring their children ‘stand a head taller’ is a priority for many parents, who worry that if their children do not grow tall enough, it will affect their self-confidence. What is the key to a child’s height growth? We have invited paediatric specialist Dr Xu Ziyun to share the key factors for promoting height growth, including a balanced diet, sufficient and high-quality sleep, and appropriate exercise choices. Dr Xu explains that 70–80 per cent of a child’s height is determined by family genetics;whilst 20–30 per cent is influenced by environmental factors. If a child’s height lags behind that of their peers, there is no need to lose heart. Although one cannot alter one’s genetic makeup, it is possible to ‘make up for shortcomings through diligence’ to help the child reach their expected target height (Reference:Child weight standards)。
The golden 10 years for children to grow tall?
It is often said that the first 10 years of a child’s life are particularly crucial for their height. Dr Xu explains that this is because children grow most rapidly up to the age of 10, and will reach 80 to 85% of their final adult height before they enter puberty.
Children's growth rates vary at different stages. In the first year after birth, infants experience a rapid growth spurt, increasing their height by 20-30 cm. After the age of one, up until puberty, their height growth gradually slows down. For children aged 4 to 9, height should increase by 4 to 6 cm per year. Growth during this period is influenced by nutrition,Growth hormoneand factors such as thyroxine. Puberty is another period of rapid growth, generally starting between 10 and 12 years of age and finishing between 14 and 16 years of age. Girls' puberty starts and finishes earlier, with an average height increase of 7 to 8 centimetres per year; boys, on the other hand, grow by an average of 8 to 9 centimetres per year. After puberty, height is almost fixed.
Parents can refer to "growth charts" to assess their child's growth rate.
Are growth plates the key to growing taller?
Growth plates are located at the top and bottom ends of bones and continuously multiply to form cartilage tissue. When cartilage calcifies, it becomes hard bone, causing bones to lengthen. Therefore, children's height largely depends on the formation of growth plates. The average age for males and females to complete development is 16 and 14 years old, respectively. Thus, before puberty arrives, parents should encourage their children to develop good lifestyle, dietary, and exercise habits to help them grow more completely.
Promoting exercise choice? Exercise duration and frequency?
If you want children to grow taller, they should do more full-body stretching exercises, such as ball games and swimming, to stimulate growth plate cell differentiation, bone tissue, and endocrine growth, helping them to grow taller. Conversely, excessive or weight-bearing exercise may affect children's joint and cartilage development, and tendon growth.
- Preschoolers up to the age of 4 are recommended to engage in 3 hours (cumulative) of physical activity per day. Playing with toys and walking promote gross motor skill development.
- Children aged 5 and above are recommended to engage in at least 60 minutes of moderate-to-vigorous intensity physical activity daily (accumulated). "Moderate intensity" refers to physical activity where breathing and heart rate slightly increase, with light sweating, but without feeling strenuous. "Vigorous intensity" refers to physical activity where breathing is rapid, the heart rate is very fast, and there is significant sweating, causing a strenuous feeling. At least 3 sessions of vigorous intensity activities should be undertaken weekly, including bone and muscle-strengthening activities.
How much does adequate sleep affect height gain? When is growth hormone secretion highest?
Aside from exercise, rest has a huge impact on a child's growth.Growth hormoneIt is a protein secreted by the anterior pituitary gland that helps muscle and bone growth, and fat breakdown. Growth hormone secretion peaks twice, mainly between 10 p.m. and approximately 2 a.m., with another smaller peak between 5 a.m. and 7 a.m. Whenever children enter deep sleep during these times, their bodies can release the most growth hormone, aiding growth. However, insufficient sleep or sleeping too late may affect height growth.
A report by the World Health Organization states that children's growth rates vary throughout the year, with the fastest growth occurring in spring and summer. Is this report applicable to children in Hong Kong?
The World Health Organization reports that children's height increases at different speeds throughout the year. They grow an average of 22 millimetres in spring and summer, which is 2 to 2.5 times faster than in autumn. Looking at the whole year, May is when they grow the tallest, averaging 7.3 millimetres, while October is the slowest growth period, averaging 3.3 millimetres.
Dr. Xu explained that because the summer days are longer and the summer holidays offer more leisure time, allowing children to exercise and rest with a more relaxed mood, it is beneficial for their growth and development, hence the popular saying that spring and summer are the golden periods for height growth.
New medical technology for height growth?
The medical community has certain reasons forDwarfismChildren treated with "growth injections" for short stature, such as those born small for their gestational age, genetic conditions, or children with idiopathic short stature, or pathological short stature such as chronic kidney disease, Turner syndrome, Prader–Willi syndrome, etc. The so-called "growth injection" is growth hormone, a protein that stimulates the growth plates of bones that have not yet closed. Growth hormone has been used for over thirty years, and numerous medical reports have confirmed its good therapeutic effect. A small number of children may experience side effects, such as headaches, muscle pain, gastrointestinal discomfort, and high blood sugar. Parents who notice their child is abnormally short for their age can consult a specialist doctor for an assessment.
Paediatric specialist Dr. Xu Ziyun
