why do I have to sleep with the light on?
Sleep Problems

Why Can’t I Sleep Without A Light On?

Many people fear darkness and find sleeping with the lights out unsettling.

You may be used to sleeping in light conditions, perhaps because you work by night and sleep by day, or are concerned about trips and falls if you wake at night and need to move around the room.

The main concern surrounding sleeping with lights on is the impact on your circadian rhythms.

The human body relies on light-dark cycles to regulate hormones, so artificial light suppresses the release of melatonin, the “sleep hormone.”

Without melatonin at night, it’ll be hard to doze off and remain asleep.

Why Do I Prefer to Sleep with the Lights On?

Here are the likely reasons you find sleeping with the lights off difficult:


Nyctophobia is a fear of darkness at night. This term is used interchangeably with achluophobia, but the latter term refers to a fear of all forms of darkness, including closets, crawlspace, and attics.

Most people with nyctophobia deal with their fears by sleeping with lights on. However, there are various nyctophobia solutions, including exposure therapy, virtual reality simulations, and hypnosis.

Why do I struggle to sleep in the dark?

Light Exposure

Most people associate darkness and night with sleep, but not everybody. If you work at night and sleep during the day, you may consider natural light part of your rest routine.

Shift work can cause problems with the body’s circadian rhythms. Chest refers to this as Shift Work Sleep Disorder (SWSD,) which can lead to trouble sleeping as your body is confused.

Getting enough sleep is the most important thing you must tackle, so if that involves dozing in bright light, this should be the objective. Try to coach your body and brain to sleep in darkness with an eye mask.

Light pollution can leave people accustomed to sleeping with illumination. If you live in a big city, you may be used to streetlamps bringing light into your room at night.

Close the curtains, drapes, or blinds, and cover your eyes until you welcome darkness.

Safety Concerns

If you regularly wake in the night and need to move around the bedroom, perhaps to use the bathroom, you may be concerned about slipping or tripping over trailing cables or sleeping pets in the dark.

This concern is common in older adults with nocturia. Young parents may also be concerned about leaving the room quickly to deal with a crying baby.

Consider keeping a flashlight by the bed and using this instead of keeping the lights on at night.

Is It Better To Sleep with The Lights On or Off?

Sleep experts believe you should sleep with the lights off, plunging the bedroom into complete darkness. This will make falling asleep and remaining that way for 8 hours easier.

It’s common to start feeling sleepy toward the end of the day after the sun sets. While part of this is due to fatigue caused by activity throughout the preceding hours, it’s also a hormonal response.

When exposed to increasingly dim lighting, the pituitary gland in the brain releases melatonin.

Melatonin encourages the mind and body to relax, blocking the production of cortisol – responsible for feelings of stress and anxiety – and loosening the muscles.

By gradually reducing exposure to light in your home, your body will be steadily flooded with melatonin. When lying in a dark room, you’ll be ready to fall into a natural sleep.

The more artificial light you expose yourself to, the harder it’ll be to produce melatonin.

Clinical Endocrinology warns that exposure to overhead lights can delay melatonin peaking for up to 2 hours, significantly disrupting your sleep schedule.

If you sleep for 8 hours, you’ll complete 4 or 5 sleep cycles, enhancing your chances of feeling physically and mentally refreshed upon waking.

If you fall asleep late due to excess lighting in the bedroom and still need to wake up at the same time in the morning, you’ll reduce your sleep cycles.

While we can function on around 4 hours of sleep, accruing sleep debt will take a toll on you.

Advantages of Sleeping with Lights On

Sleeping with the lights on offers few benefits, aside from offering comfort from a fear of the dark or introducing familiarity if you’re used to a bedroom with external light.

It is a myth that sleeping with the lights on will deter bed bugs or other unwelcome visitors like cockroaches, spiders, or ants. Insects and arachnids dislike bright light, but not enough to prevent them.

Sleeping with the lights on can’t prevent sleep paralysis or night terrors. It encourages the brain to remain active and produce cortisol, making bad dreams and hallucinations more likely.

The only advantage of sleeping in a well-lit room is if you want to take a brief nap.

Drawbacks of Sleeping with Lights On

Exposing yourself to illumination overnight can place your long-term health at risk. Other than insomnia, hazards associated with sleeping in a well-lit room include the following:

Eye Damage

Constant exposure to bright light can affect your eyes, hastening the decline of vision that comes with age. The BMJ explains how this concern first arises in children but can continue long into maturity.

The longer you leave your lights on, the more sensors in your retinas will become overstimulated.

Be careful if you feel that you no longer notice bright lights. This suggests your eyes are growing desensitized, which can point to increasing short-sightedness.

Failing to shut down the lights at night can cause headaches and migraines. Cool lights, including the blue light emitted by screens and electrical appliances, will cause the most issues.

If you keep the lights on at night and struggle to sleep well, you’ll experience aesthetic issues around the eyes. Sleep debt can cause dark circles under the eyes.

Slower Physical Development

Children may ask to sleep with the lights on because they fear the dark. Unfortunately, sleeping in an illuminated bedroom can affect growth.

A growing body undergoes’ growth spurts’ during slow-wave sleep – the third stage of a sleep cycle. A child may not experience enough slow-wave cycles to grow appropriately.

Obesity and Associated Hazards

Sleep warns that keeping the lights on overnight can impact your heart and blood pressure. Overnight lighting can also lead to weight gain, a contributing factor for heart disease later in life.

It can increase insulin resistance, which leads to a risk of diabetes, especially if you’re overweight.  

The human body burns calories while we sleep. According to the Journal of Pineal Research, darkness and the release of melatonin speed this process up.

why do i sleep better with lights on?

Mental Health Problems

We can all be grumpy and irritable if we don’t get enough sleep.

The American Journal of Epidemiology links night lighting with the symptoms of depression. Even a tiny amount of light in a bedroom can impact our mental health.

Illumination above 5 luminous flux per unit (lux) increases depressive episodes. If you light a candle and stand a foot away, the flame will produce 10 lux.

Children and the elderly are most at risk of mental health issues due to night lighting.

Is It OK To Sleep with Dim Light On?

Consider using a night light if you want to sleep with some illumination. Night lamps offer a softer, lower light than a traditional or overhead light.

Avoid cool colors like white, yellow, or blue when using a night light.

Warm shades, especially red, are believed to cause fewer restrictions in melatonin production. The Journal of Athletic Training even claims that red light therapy improves sleep.

Sleeping in a dark, cool room will significantly improve the quality of your rest.