Can't sleep at night

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By Dr Simon Kyle

It is not uncommon to find oneself wondering, 'why can't I sleep' at night. This thought can be extremely overwhelming in the dark, when it seems everyone else in the world is already sound asleep. Thinking about not sleeping can then lead to worry, feelings of hopelessness, fears about how one will cope the next day.

Could the following factors be contributing to your sleepless nights?


We know that certain lifestyle factors can greatly influence how one sleeps once the nighttime rolls around.

Nicotine, for example, can make it harder to wind down in the evening and get to sleep. It also causes frequent short awakenings during sleep that one might not be aware of but which will have an impact on one's sleep quality.

Caffeine is another big offender which, if ingested later in the day, can lead to poorer sleep. People are often advised to stop drinking caffeinated beverages after 6 or 7pm, however, as caffeine may be metabolized at a slower rate as we age, you may need to experiment to find the right time for you.


Stress has been shown to interfere with one's ability to fall asleep and stay asleep. It may also reduce the length of time spent in deep sleep and increase time spent in the lighter phases of sleep, making our sleep more vulnerable to disruption due to light or noise.

Light levels

Melatonin is a naturally occurring hormone which the brain produces in the late evening and throughout the night. It is associated with the light-dark cycle and promotes the onset of sleep.

Strong light can inhibit the production of melatonin and delay sleep onset, leaving you counting sheep well into the night.

There is emerging research that light from a standard laptop directly before bed may disrupt melatonin production and delay sleep onset.

You may find it helpful to dim the lights in the period close to bedtime and, if you are easily disturbed by light, it may be time to invest in a sleep mask.

Daytime naps

Napping during the day has, in recent years, undergone something of a renaissance, with more companies allowing employees to take power naps within office hours. However, whilst napping during the day may work for some people, they may also be preventing you from sleeping at night.

Avoiding naps during the day may prepare you better for a continuous, longer sleep at night. Instead, you might prefer to introduce a stimulating activity, such as a walk, at the point during the day when you start to get tired.

Irregular sleep schedule

An irregular sleeping pattern is not conducive to good sleep. For this reason, poor sleep may be more common in shift workers with variable working hours.

Whilst some people are able to adjust well to irregular hours, research suggests that people with an irregular sleep schedule may be more likely to experience sleep disturbance, fatigue, work-related accidents, cardiovascular problems, gastrointestinal problems and, in women, breast cancer.

Light is crucial to our natural 'body clock', so your sleep may benefit from exposure to light in the morning and avoiding brief light later in the evening.

Filed under: Can't Sleep?