Why Sleep in the Dark? The Connection Between Light at Night, Hormones, Sleep Quality, and Skin Health

We are careful about proper nutrition, physical activity, drinking water, and a skincare routine, but there is one habit we do not always give enough attention to.

The environment in which we sleep.

Think about your bedroom for a moment.

Is it really dark at night?

Or does light from the street lamp penetrate through the curtain, a small TV light is on, the phone lies next to the bed, and every so often its screen lights up the room?

We may think that if the eyes are closed, the light no longer matters.

But our body is sensitive to light and darkness much more than we think.

Light is one of the most important signals by which the brain sets our biological clock.

And this clock affects not only sleep, but also hormone secretion, metabolism, and many processes occurring in the body.

Therefore I believe a dark sleeping environment is one of the simple things we can do to support our health.

Our body is designed to distinguish between day and night

For most of human history, life proceeded according to the natural cycle of light and darkness.

Sunlight signaled to the body that the time had come to be alert and active, and darkness signaled that night was approaching.

Even today, despite electric lighting, screens, and the modern lifestyle, our biological system continues to operate according to these signals.

In the brain there is a system that regulates the central biological clock, and it receives information about light through the eyes.

This information helps the body coordinate between waking and sleeping hours and various physiological processes.

Therefore exposure to light in the evening and night hours can affect the timing of the biological clock, especially when it comes to strong light or light rich in short wavelengths, like the blue light emitted from screens and certain lighting sources.

Melatonin: the hormone that signals to the body that night has come

One of the most important hormones in this context is melatonin.

Melatonin is produced mainly in the pineal gland in the brain, and its secretion usually rises in the evening hours, when the environment darkens.

Its central role is to convey to the body information about biological time and help it prepare for sleep.

Exposure to light during the night hours can suppress or delay melatonin secretion, according to the intensity of the light, the duration of exposure, and the type of lighting.

This is one of the reasons it is recommended to reduce strong lighting and avoid prolonged screen use close to bedtime.

But it is important to me to be precise.

Not every small light in the room necessarily causes a significant disruption in melatonin secretion, and not every light exposure affects all of us in the same way.

Even when the eyes are closed, sufficiently strong light may penetrate through the eyelids and arouse responses in the light-sensitive system, but the eyelids greatly reduce the amount of light reaching the eyes.

Therefore there is no need to fear every small point of light, but it is definitely worth reducing unnecessary light exposure during the night.

Melatonin is not only a sleep hormone

Melatonin also has additional interesting biological properties.

Studies indicate that it participates in processes connected to protection against oxidative stress and regulation of cellular activity.

In the skin too there are local mechanisms connected to melatonin.

In laboratory studies, melatonin was found to potentially participate in protecting skin cells against oxidative damage.

At the same time, it is important to distinguish between these findings and the claim that sleeping in the dark prevents wrinkles or directly repairs skin damage.

Research in the field is still developing, and there is currently no proof that a dark room alone slows skin aging.

But good sleep is definitely an important part of a lifestyle that supports the health of the body and the skin.

What happens to our hormones during sleep?

Sleep is not only a time when we stop being active.

During the night many processes of regulation, recovery, and maintenance occur in the body.

Some of these processes are connected to hormones whose secretion changes throughout the day.

Growth hormone

In adults, a significant part of growth hormone secretion occurs during sleep, especially in the deep sleep stages.

This hormone participates in processes connected to tissue maintenance, metabolism, and regulation of growth and repair processes.

At the same time, it is important to know that growth hormone secretion is connected mainly to the structure of sleep and its stages, and not to darkness in itself.

Cortisol

Cortisol is a hormone that participates in the response to stressful situations, but it is also essential for the proper functioning of the body.

Cortisol levels have a daily cycle.

Usually they are relatively low in the first part of the night, rise toward morning, and help the body prepare for waking.

Prolonged disruptions in sleep and the biological clock may affect this cycle.

Insulin and blood sugar levels

Studies found that lack of sleep and disruption of the biological clock can affect the body's sensitivity to insulin and the regulation of blood sugar levels.

In certain controlled studies, even exposure to lighting in the room during sleep was found to possibly affect metabolic measures the next day.

But it is still unclear to what extent such effects occur in normal living conditions, and what their health significance is over time.

Hormones connected to hunger and satiety

Insufficient sleep can also affect the feeling of hunger and appetite.

In certain studies, changes were found in hormones like ghrelin and leptin following sleep restriction.

At the same time, the findings are not uniform across all studies, and the effect on appetite is more complex than a change in one hormone.

I think the important message is not that every night with a little light causes hormonal disruption, but that sufficient and regular sleep supports many systems in the body.

And what is the connection between sleeping in the dark and skin health?

We already talked on the blog about the importance of good sleep for the appearance of the skin.

But there is another interesting point.

Our skin cells also have local biological clocks, affecting the timing of various processes throughout the day.

The activity of DNA repair mechanisms, cell division, and skin barrier function changes according to biological rhythms.

The skin does not renew only at night, and the repair processes do not stop during the day.

But the biological clock helps coordinate this activity with the day and night cycles.

Studies found a connection between poor sleep quality and slower recovery of the skin barrier after damage, and also certain connections to signs of skin aging.

Therefore when we talk about a skincare routine, it is worth remembering that sleep habits are also part of the picture.

A good serum and a suitable moisturizer can support the skin from outside.

Good sleep supports the proper functioning of the body from within.

Does sleeping with a light on really affect health?

In recent years researchers are examining the effects of exposure to artificial light during the night.

In some studies, a connection was found between prolonged exposure to light at night and disruptions in sleep and metabolic measures.

There are also observational studies that found connections between exposure to light at night and various health conditions.

But it is important to beware of exaggerated conclusions.

A statistical connection does not necessarily prove that the light is the direct cause of the problem.

In addition, some of the significant evidence in the field comes from studies on shift workers, whose lifestyle includes repeated disruptions in sleep and waking cycles.

It cannot be concluded from this that a small charger light in the bedroom causes the same risks.

And yet, since light is a significant factor in regulating the biological clock, reducing unnecessary lighting at night is a logical and simple habit.

How dark should the bedroom be?

I recommend aiming for a bedroom as dark as is comfortable and safe for you.

There is no need to perform tests like checking whether you can see your palm in the dark, and there is no single level of darkness that necessarily suits everyone.

The goal is to reduce light sources that disturb sleep or light the room unnecessarily.

A few simple things can help:

Blackout curtains

If street light penetrates the room, blackout curtains can significantly reduce exposure to it.

Sleep mask

For anyone who finds it hard to darken the room, a comfortable sleep mask can be a simple solution, especially on trips or in hotels.

Turning off unnecessary lighting

You can turn off screens, hide strong indicator lights, and move away light sources that disturb sleep.

Reducing phone use before sleep

It is worth reducing screen use in the hour before sleep, especially if the content is stimulating or the lighting is strong.

If you do use the phone, you can dim the screen and activate a warmer lighting mode.

Dim lighting when getting up at night

If you need to get up for the bathroom or to drink water, it is better to use dim lighting that allows safe orientation, instead of turning on a strong light.

It is especially important to prevent falls, so there is no need to walk around in total darkness.

And what about morning light?

Here comes the complementary part of the story.

Exactly as it is worth reducing unnecessary light at night, exposure to natural light during the day, especially in the morning hours, can help set the biological clock.

Morning light provides the brain a clear signal that the day has begun.

It helps time the waking and sleeping cycles and may support alertness during the day.

Therefore I love thinking of good sleep as part of a complete cycle.

Light during the day hours.

More moderate lighting in the evening.

And a dark environment during sleep.

There is no need to fight nature. Sometimes it is enough to adapt our habits to it a little.

Do we need to sleep in total darkness?

Not necessarily.

A dark room is usually a recommended sleeping environment, but there is no need to turn the subject into another source of stress.

If you need dim night lighting to feel safe or to orient yourselves in the room, you can use it.

If a small light does not disturb your sleep, there is no reason to automatically assume it harms your health.

What matters more is the overall picture: the duration of sleep, its quality, the regularity of sleep hours, and light exposure throughout the day.

And for anyone suffering from persistent sleep difficulties, it is worth checking the cause and not assuming the problem stems only from the lighting in the room.

Good sleep is part of self-care

I believe we sometimes look for complex solutions to things that can be improved through simple habits.

We invest in skincare products, supplements, and various activities to maintain our health and appearance.

But we do not always give enough importance to the hours when the body is supposed to rest.

Sleep is not a luxury.

It is a basic biological need, affecting concentration, mood, metabolism, and many processes in the body.

And when we take care of a suitable sleeping environment, we give ourselves better conditions for rest.

Our approach at OrOrgani

At OrOrgani we believe true care combines treating the skin from outside with life habits that support health from within.

We can be careful about facial cleansing, a quality serum, a moisturizer, and sun protection, but it is no less important to remember the basic needs of the body.

Sufficient sleep, balanced nutrition, physical activity, drinking, and habits that allow us to relax.

Sometimes a small change, like darkening the bedroom or turning off the phone a little earlier, can help us create a calmer, more pleasant evening routine.

There is no need to look for magic solutions.

We need to give the body the conditions it needs.

In summary: Let the night be night

Our body knows how to distinguish between light and darkness, and this difference is important for the functioning of the biological clock.

Exposure to light at the wrong time can affect melatonin secretion and sleep timing, so it is worth reducing unnecessary lighting during the night hours.

But there is no need to fear every point of light or to believe that total darkness is the secret of youth.

The real secret is to allow the body as natural a cycle as possible of light by day, darkness by night, and good sleep between them.

So tonight, before you get into bed, look around you for a moment.

Maybe you can turn off one more small light, close the curtain, and put the phone aside.

Sometimes it is precisely the things we turn off that help us feel better in the morning.

With love,
Nurit
OrOrgani

With love,
Nurit Rozenblat
OrOrgani

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