What are the benefits of leaving a night light in the child's room to sleep? There are so many benefits.
It is convenient to feed and change the baby's diaper; it is convenient to observe whether the baby has spit up, overflow, or choke; it is conducive to using a breast pump and going to the toilet.
All of this is based on not having to turn on the headlights so as not to affect the baby's sleep, but as everyone pays more and more attention to the problem of light pollution, there are some voices that turn on the night lights will also affect the baby's sleep, height, and even sexual development.
What's going on here? Can the night light be turned on? Today we talk about the impact of night lights on sleep, and in the next issue we will talk about the impact on height and sexual development.
Too long not to look at the version
1. A small night lamp with low light intensity (within 3lx) should be selected, more than 2.0m from the bed, placed in a position lower than the bed surface, not directly hitting the face and not facing the eyes;
2. When the child is young, it is convenient and harmless to leave a small night light, but when you grow up, respect the child's own wishes, turn it off if you don't need it, and turn it off after you fall asleep.
No.1
What is light pollution? What are the dangers of light pollution?
Only when there is light can all things flourish.
In general, in the summer, under direct sunlight, the light intensity can reach 60,000 to 100,000 lux (lux, legal symbol lx, light intensity unit), outdoor 1000 to 10000lx in the shade, 100 to 500lx indoors in summer, and 0.2lx under the full moon at night.
Although the light intensity can be very strong, it is a full-fledged natural light, not light pollution, so there is light ≠ light pollution.
With the modernization of society, the office buildings of shopping malls are more and more bright, the headlights are getting brighter and brighter, the glass exterior walls are more and more, the indoor walls are becoming more and more white, and the mobile terminal screens are becoming more and more blind.
The "white light pollution", "artificial daylight", "colorful neon", and "city that never sleeps" caused by these artificial light sources will lead to light pollution, which is harmful to health, harmful to the eyes, affects the mood, and can even induce cancer.
No.2
How to judge whether your city has light pollution?
U.S. medicine defines light pollution as light pollution at night at a height of 14 lx or about 10% higher than the normal nighttime sky brightness level. Astronomical statistics show that about 7,000 stars can be seen in the clear, cloudless night sky without light pollution.
According to this standard, I have lived in Shenzhen and Wuhan, and I can't even find 10 stars under the same clear and cloudless situation, and this brightness is more than 10% higher than the normal night sky brightness, and there is light pollution in the environment.
No.3
What is the light intensity in the room? Do you need that bright light at night?
According to China's "Architectural Lighting Design Standards", the light intensity of living rooms and dining rooms is basically enough at 100 to 300lx. Ordinary incandescent lamp 1w can emit about 12lx of light, with a lampshade, the distance of 2.0 ~ 2.5m, 3w bulb can provide 10lx of light.
How strong is the night light left when sleeping?
Pro-test a treasure, a cat, a small night lamp have a thick lampshade, the bulb is not directly exposed, the power is 0.8-2w, the light intensity is 2 ~ 5lx, a small number of 3w night lights can be artificially adjusted brightness. Obviously, the light intensity of the night lamp is far lower than the national standard, not light pollution, rest assured!
No.4
How does light intensity affect sleep? Can the night light be turned on?
First, the body's circadian rhythm system signals the pineal gland 90-120 minutes before our habitual bedtime to produce melatonin, followed by sleepiness and finally sleep. Theoretically, as long as there is light, melatonin secretion will be reduced, which will affect sleep.
But avoiding light intensity and discussing the effects of light is all hooliganism, all unscientific. How does light intensity affect melatonin secretion?
First, experts measured melatonin concentrations in children (elementary school students) and adults at night in dim light (<30 lx) and moderate light (consistent with below) (580 lx).
Moderate brightness light (580 lx) was found to have a significantly greater inhibitory effect on melatonin in children than in adults, with twice the inhibition rate in adults, and indoor dim light (< 30 lx) also significantly inhibited melatonin secretion in children, but did not inhibit adults.
Compared with the national standard, is the light intensity of 580 lx too large? There is no hurry, and some experts have compared the lower light intensity.
Late-night exposure to indoor bright light (<200lx) and melatonin secretion in dim light (<3lx) (exposure began 8 hours before bedtime, more than 5 consecutive days), compared with dim light, exposure to indoor bright light before bed not only inhibits melatonin secretion, but also leads to a delay in melatonin action in 99.0% of individuals, and the duration of melatonin is shortened by about 90 minutes!
What's more, exposure to bright indoor light during sleep also inhibited melatonin secretion by more than 50% of the majority (85%) of the subjects.
These results suggest that bright indoor light has a profound, all-round inhibition of melatonin levels and shortens the duration of melatonin.
Therefore, sleep does not turn on the lights, and it is difficult to sleep when the lights are turned on.
Please pay attention to the light intensity again, the above-mentioned research has an impact on the light intensity of 580lx, 200lx, 30lx (of course, there are higher light intensity studies, and the general indoor light intensity is rarely obtained, so there is no one list), < 3lx has little impact.
So when we sleep, we should try to control the light intensity below 3lx, the light intensity of the night light is mostly 2 ~ 5lx, we choose the night light below 3lx or can be artificially adjusted brightness, which has little impact on sleep.
But turning on the lights (living room headlights) still has a big impact, so instead of turning on the headlights, it is better to leave a small night light.
No.5
How do babies of different ages use lamps scientifically?
Newborn babies, small babies
Let's first look at what the baby's circadian rhythm is, in fact, we overestimate the effect of light on the newborn.
For newborn babies, most of the day after birth is in a state of sleep, day and night, up to 14 to 17 hours a day.
In addition, the circadian rhythm of melatonin secretion in babies within 3 months of age has not yet been established, although the baby within 1 year old is not obvious, with age, the circadian rhythm is more and more obvious, at the same time, the total daily secretion of melatonin decreases, and the total sleep time of the whole day gradually declines.
Studies have shown that in the neonatal ward, the impact of artificial light sources on the baby's circadian rhythm does not seem to be obvious, but the various "hands-on" and drug use of medical staff, such as examining the baby's body, puncture, intubating, sedatives, and drugs that excite the respiratory center, have a greater impact on the baby's circadian rhythm.
In fact, the artificial light source in the home has little impact on the baby's sleep, and the baby's sleep is more related to the contact with screen media, the mental pressure of parents, and the work and rest of parents.
School-age children
For older children, whether or not a night light affects sleep actually varies from person to person.
Some children are very sensitive to light, and there are small night lights that will indeed be reluctant to sleep, sleep, and sleep unsteadily, thereby prolonging the time to fall asleep and affecting the quality of sleep.
Some children are already familiar with this kind of weak light, turning on the night light is more secure, but falling asleep faster, and in the dark environment, the children's rich imagination imagined a variety of "demons and ghosts", fell into fear, and could not sleep for a long time; then for these children, it is still a small night light to guide the dreamland.
In summary, the night light can of course be turned on, as long as the night light is used correctly, which is convenient for care and does not affect the child's sleep.
Instead of tangling with the night light, it is better to respect the circadian rhythm of the human body with the child, put down the mobile phone, take off the iPad, turn off the TV, turn off the computer, work and rest regularly together, sleep well at night, and accompany high-quality during the day.
bibliography:
1.Pankaj C Patel. Light pollution and insufficient sleep: Evidence from the United States. [J] Am J Hum Biol.2019;31:c23300
2.Zeitzer J.M., Dijk D.J., et al. Sensitivity of the human circadian pacemaker to nocturnal light: melatonin phase resetting and suppression. [J] Physiol.2000;526,695-702.
3.Higuchi Shigekazu, Nagafuchi Yuki, et al. Influence of light at night on melatonin suppression in children. [J] Clin Endocrinol Metab.2014V99N9:3298-303
4.Gooley Joshua J, Chamberlain Kyle, et al. Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans. [J] Clin Endocrinol Metab.2011V96N3:E463-72
5.Shinohara Hitomi, Kodama Hideya. Relationship between circadian salivary melatonin levels and sleep-wake behavior in infants. [J] Pediatr Int.2011V53N1:29-35
6.Huang XiaoNa, Wang HuiShan, et al. Development of sleep/wake patterns in infants during the first 12 months of life. [J] Zhonghua Er Ke Za Zhi.2009V47N7:499-503.
7.Morales-Munoz Isabel, Partonen Timo, et al. The role of parental circadian preference in the onset of sleep difficulties in early childhood. [J] Sleep Med.2019V54N:223-230.
8.Cremer Martin, Jost Kerstin, et al. Immediate effects of phototherapy on sleep in very preterm neonates: an observational study. [J] Sleep Res.2016V25N5:517-523.
9.Vijakkhana Nakul, Wilaisakditipakorn Tanaporn, et al. Evening media exposure reduces night-time sleep. [J] Acta Paediate.2015V104N3:306-12.