"Sleep is the key to a kid’s height", "Sleep quality is essential for height growth"... Opinions like this are common in real life and online, and are generally accepted by everyone. One of my aunts was convinced of this. I remember that every time my cousin came to play at home when I was young, my aunt was afraid that we would lie in bed at night and chat and not sleep, so every day before going to bed, she would remind us repeatedly, "Don’t keep chatting, go to bed quickly, or you will not grow if sleeping too late! "

In the past, I never considered the authenticity of this question. Until I was studying for a Ph.D., my professor put forward in the class that, academic circles had been debated for many years about whether genes determine height or nutrition determines height... At that time, I thought, oh, doesn't sleep determine height?

As the Ph.D. project continues, I have been investigating the related factors that affect the development and health of children, and I have become more and more aware of the factors that affect the growth and development of children, and no longer believe in the superstition of sleep.

Later, I had my first child, who has a poor quality of sleep, but her height development has always been great, and her height reference curve is about 90th. The second child slept much better, but his height was around 70th. Is it the first child to develop better? Not really. The baby's development is not about who is taller or heavier. It is about comparing with yourself. The curve is approximately parallel to the reference curve, and a stable trend means good development. The more I communicate with many parents and friends, the more I find that their greatest anxiety about sleep comes from the misunderstanding that "the poor sleep of the baby affects height".

So far, I have found that not only "poor quality of the sleep affects height", "growth hormone therapy" has also become popular.

Indeed, "growth hormone mainly reaches the peak of secretion after falling asleep", but it doesn’t mean that the child will not grow taller if he sleeps late or if he wakes up frequently at night. The nocturnal growth hormone measurement test requires a blood draw every half an hour before continuing to sleep. The conclusion that "the peak of growth hormone secretion is in the state of sleep" itself is the result obtained when sleep is constantly interrupted, so it cannot be regarded as "wake up frequently, with little growth hormone secretion". Both healthy babies and children may wake up at night for various reasons: whether the child is sick, whether the child sleeps too much during the day, whether he wakes up from a dream.

I cannot accept the use of sleep anxiety and height anxiety to promote the growth hormone therapy which requires strict indications and application standards. What also makes me unbearable is that in a "science popularization" video, The narrator used a child with a tumor who could not sleep well to explain that "sleep deprivation is the cause of poor height development." What kind of logic is this! Seeing this kind of "science popularization", I very much hope to cultivate children's logical thinking ability, so that they not be fooled in the future.

Illness, especially a major disease like a tumor, itself affects growth and development! We often say that good nutrition, proper exercise, and adequate sleep have a positive effect on health. Health is guaranteed, children can develop normally.

What is the relationship between sleep and height?

Because people's secretion of growth hormone increases during sleep, many experts regard sleep as the first element that affects children's height. But there is no evidence to support this view. Up to now, research on sleep patterns and height growth is limited. In these few studies, sleep has not been found to have a "critical" effect on height, and some studies have not even found an association between the two.

A study conducted in England and Scotland involving more than 5,000 children aged 5 to 11 found that after adjusting for other factors that may affect height, there was a weak negative correlation between sleep and height (Those children who sleep less are taller). The researchers believe that the research evidence does not support the view that "the longer the child sleeps, the taller they will grow"; and concluded that sleep time is unlikely to have an important effect on development.

Another study conducted in Switzerland also found no correlation between sleep time and children's height. Although only 305 children were included in this study, the researchers tracked these children from 1 to 10 years old (followed up once a half year before age 2 and once a year after age 2). The results show that there is no correlation between sleep time and children's height at any stage from 1 to 10 years old. The final conclusion of the researcher is that the length, characteristics, and state of sleep are very different between infants and children. Therefore, when solving sleep problems, individualized suggestions need to be adopted, and unified suggestions are not suitable. When trying to get the child to sleep well and get more sleep, more consideration should be given to the individual needs of the child.

In the United States, a cohort study involving more than 2,000 adolescents aged 12-16 did not find an association between sleep time and the rate of height growth.

However, some studies have found a positive correlation between sleep time and growth. For example, in a cohort study conducted in Singapore, the researchers tracked and measured 899 babies at 3, 6, 9, 12, 18, and 24 months of age. The results showed that in the first 2 years after birth, there is a positive correlation between sleep time and body length. However, the strength of this association is weak.

In fact, many studies have found that lack of sleep can lead to obesity in children and adults. Sleeping less will make you fat, but the current evidence does not support “sleeping less will make you short”.

Do not use growth hormone casually

The growth hormone can promote cell regeneration and human development. It is a very important hormone in the growth and development of children. If the secretion of the growth hormone is insufficient, the child will experience growth retardation. However, growth hormone therapy has tended to be abused in the past two years. Many children of relatives and friends around me have been suggested to use growth hormone therapy. However, are there really so many children with insufficient growth hormone secretion?

The distribution range of healthy height is actually very wide. From the growth curve, the height between 3th and 97th (or ±2Z value) is a normal height.

If the child really has stunted growth, you need to see a doctor and investigate the cause first. If there are no other physical symptoms, the doctor's first consideration should be whether the child's diet is reasonable. Parents must be wary of doctors who treat their children with growth hormone when they see that their children are not tall enough. Abuse of growth hormones can interfere with the body's endocrine system. Too much foreign hormones can make the glands mistakenly believe that the body's hormones are sufficient, and stop normal secretion or even shrink.

Growth hormone therapy is a treatment method. If you want to use it, you must first find out if your child really needs it.

What are the main factors that determine height?

What can be certain is that genes are the strongest factor in determining height, accounting for approximately 60% to 80% of all factors. Genes determine all aspects of our life and development. It can be said that when each of us is born, the range to which we can grow has been roughly determined by genes.

However, although genes cannot be changed, there are some acquired factors that independently affect height and modify the potential of height determined by genes. Among these acquired factors, the most important that currently known is nutritional status.

A balanced and age-appropriate diet, including a reasonable intake of carbohydrates, protein, fat, vitamins, and minerals, can affect the growth of children. If genes determine your development and healthy programming, nutrition is the raw material that can be used in genetic programming. Children with insufficient nutritional intake may be stunted, but when nutrition is improved, the development of the child can also be improved.

Illness can also affect your child's development. In addition to affecting the child's appetite (or nutrition), the illness may also affect the child's sleep and hormone levels. Hormones are substances that transmit signals between body systems. They affect all aspects of our health, from growth and development and metabolism to blood pressure and mood. Almost all hormones can affect growth to some extent, but some of them have more important effects, such as growth hormone, thyroid hormone, cortisol, insulin, androgen, testosterone, estrogen, estradiol, etc. Hormones affect the development of children, not just growth hormones.

Writing this article is not to deny the importance of sleep for children, but to tell everyone that letting go of anxiety, the effect of sleep on children's height is not "so" important.

To ensure that the height of the child is within the range determined by the gene, and to perform to a better level, what is needed is:

  • Balanced and adequate nutrition,
  • Exercise more, especially outdoor activities,
  • Reduce stress and sleep well,
  • Vaccination on time.