Exploring the secrets of children's height development: scientific prediction and analysis of influencing factors

Author: Zhang Zhixin, Chief Physician of China-Japan Friendship Hospital

Reviewer: Wu Xueyan, Chief Physician, Peking Union Medical College Hospital

When discussing the issue of height development of infants and children, parents generally show great interest, especially when the child is born or even during pregnancy, they begin to pay attention to the height range that the child may reach in the future.

Genetics is recognized as one of the important factors that affect a child's height development. So how can we roughly estimate the height range of a child when he or she grows up based on the height of his or her parents? In addition to genetic factors, what other factors will affect a child's height? Next, we will explore this in depth.

1. How to predict a child’s future height based on his or her parents’ height?

Although a person's height is affected by many factors, it generally follows certain rules. In order to more scientifically assess a child's future height potential, researchers have summarized a series of simple height prediction formulas through the analysis of a large number of statistical data samples and in-depth research on genetic laws. Parents can use these formulas to roughly estimate the possible range of their child's future height. However, these predictions only represent an estimate based on statistical and genetic factors, and cannot determine a child's final height 100%.

The commonly used height prediction formula is: genetic target height for girls = (father's height + mother's height - 13cm) ÷ 2 (unit: centimeters); genetic target height for boys = (father's height + mother's height + 13cm) ÷ 2 (unit: centimeters).

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For example, if the father's height is 172cm and the mother's height is 155cm, then according to the height prediction formula, the boy's genetic target height is calculated as (172+155+13)÷2=170cm, which represents a possible central trend of the boy's future height. Similarly, if they give birth to a girl, the girl's genetic target height is calculated as (172+155-13)÷2=157cm, which is also a possible central trend of the girl's future height.

It should be noted that these estimates are not absolute. The actual height of boys fluctuates within the range of 6 cm above or below the calculated value of 170 cm, that is, 164-176 cm, which is considered normal. The height of girls fluctuates within the range of 5 cm above or below the calculated value of 157 cm, that is, 152-162 cm, which is also considered normal.

This shows that height is a quantity that varies within a certain range, not a fixed point. The assessment of this range is mainly based on the height of the parents.

2. In addition to genetics, what other factors affect height?

There are many factors that affect a child's height growth, of which about 80% are attributed to genetic factors, and the remaining 20% ​​are attributed to environmental factors. What are these environmental factors mainly?

First, food. As one of the key factors affecting height, the importance of food is self-evident. However, it is not the case that higher nutrition, more protein or fat content, can directly promote the growth of children's height. On the contrary, excessive intake of these foods may stimulate the premature development of gonads, and then under the action of sex hormones, the bone age will be closed early. This process will not only not promote the growth of children's height, but may limit their final height to a certain extent. Therefore, balanced nutrition is most beneficial to children's growth.

Second, exercise. When exercising, the hypothalamus-pituitary axis triggers the release of growth hormone, which in turn promotes the pituitary gland to secrete growth hormone. Growth hormone is a key factor in promoting bone growth and height development. Although exercise is beneficial, excessive exercise may have an adverse effect on growth. Studies have shown that the growth rate of athletes' height decreases during the training phase of the season, which suggests that excessive exercise may not help growth. Therefore, for children, moderate exercise is the key.

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Third, sleep. Growth hormone, which is closely related to height development, is secreted in pulses. Its level is relatively low during the day, and a significant peak will appear at night. Especially between 10 pm and 2 am, the secretion of growth hormone is the most vigorous during this period, and deep sleep at this time is more conducive to the secretion of growth hormone. Experimental evidence shows that if a child does not enter deep sleep during this period, the secretion of growth hormone will be significantly reduced, or even not secreted. This means that if a child sleeps too much during the day and goes to bed late at night, or has health problems such as vitamin D deficiency and eating, drinking water before going to bed, it is difficult to reach a deep sleep state, which may affect the normal growth of the child's height, so parents need to pay attention to these points of the child to ensure the child's sleep.

In addition, sleep quality is also an important factor affecting children's height development. Especially for children who snore during sleep and have sleep apnea, their chronic hypoxia will affect the secretion of growth hormone, thus hindering the normal growth of height.

Fourth, psychology. A positive attitude has a significant promoting effect on children's growth and development. Parents should pay great attention to their children's emotional state and avoid excessive pressure or forcing them to engage in activities they are not interested in, as this may invisibly hinder their height growth.

When discussing the key factors that affect children's growth, the above points are undoubtedly crucial. Of course, the use of drugs and disease status will also affect children's growth. Generally speaking, acute diseases mainly affect weight, while chronic diseases mainly affect height. For example, poor chronic renal function and congenital heart disease may interfere with children's height development for a long time. In addition, diseases closely related to the endocrine system, especially those related to the pituitary gland, the secretion of thyroid hormones, and the metabolism of key nutrients such as calcium and vitamin D may directly or indirectly affect children's height development. Therefore, parents should pay close attention to their children's overall health and consult professional doctors in time when problems are found to ensure that their children can grow up healthy and happy.