Wake up – you're not getting enough sleep. Ireland is becoming sleep deprived. We know that sleep deprivation is effectively a form of torture, so why do we stay up late and avoid going to bed?

If poor sleep leads to crankiness, fatigue, memory loss, aggression, depression and weight gain, why do so few Irish people get the hours they need? Why do so few appreciate the importance of sleep in their lives? Severe sleep deprivation leads to impaired judgment, excessive risk-taking and fatal car crashes.

Coffee is not the answer. While coffee can keep us awake after a poor night of sleep, the effects of sleep deprivation
remain.

Excessive caffeine intake can make you tremble, increase your heart rate and blood pressure. Caffeine will keep you awake but not always alert.

Some common myths about sleep:
People sleep better when they are tired.
Alcohol improves sleep.
Most people don't actually need more than four hours' sleep.
Everyone snores.
Drinking coffee cures the effects of sleep deprivation
Sleep disorders are rare.

Sleep is not a waste of time. Don’t think about sleep being the “off switch”. A good night’s sleep is the most important single factor in predicting long life – more important than diet, exercise or heredity.

Sleep is an active process, with a variety of stages that repair and regenerate the mind and body.

Every human needs eight hours of sleep to maintain health and strength. In the 1960s, the average time in bed was nine hours. That time is now reduced to 6½ hours.

There is a silent epidemic of sleep deprivation in Ireland, something we should wake up to.

Sleep definition

We define sleep as a wall between the unconscious and conscious that is immediately reversible. A person in a coma is not considered to be asleep, because they do not return to consciousness immediately after stimulation. We have no memory of sleep and no sense of time passing during sleep. Most of us don’t really know if we sleep well or not. We can recognise sleep problems in others, but not in ourselves.

We recognise at least four control factors that allow us to sleep. The first is what we call sleep pressure or sleep debt. Sleep pressure is the number of hours that one is awake without napping.

Sleep pressure gives you the feeling of sleepiness when you stay awake for 48 hours without a nap, for example. Sleep debt is the number of hours of sleep that one has missed. Sleep debt gives you the feeling of sleepiness after you sleep for less than four hours every night for a week.

The second control is called circadian rhythm, or the internal body clock. When you travel from Dublin to New York, for example, you might feel sleepy at 8pm, because your internal body clock believes the time is 2am.

The third control is the consumption of hypnotic (sleep-inducing) or stimulating (sleep-preventing) products. A strong cup of coffee before bedtime might prevent you going to sleep although it is late and you’re tired. Alternatively, when you go for an operation you might receive an anaesthetic that will make you sleep no matter how hard you try to stay awake.

And lastly, anxiety plays a part. We all remember staying awake all night before an All-Ireland final – an effect that is magnified when your own county is playing.

Thinking about the control factors can help us to explain some common sleep problems:

Example 1: A 25-year-old woman working as a medical intern has been awake and working for 24 hours without a nap (with a large sleep pressure). She might take a warm glass of milk (sleep-inducing), but she cannot fall asleep, because it is 10am. Her circadian rhythm – her internal body clock – is telling her that it is time to be awake.

Example 2: A 50-year-old businessman has been working 18 hours each day for a week and cannot fall asleep at 11pm on the evening before his presentation, because he now reali

ses that his presentation contains inaccurate information.

Anxiety is preventing him from falling asleep. This is the same reflex that keeps us alert and alive in times of danger.

Example 3: A 22-year-old man is driving home sober. It is three hours after his usual bedtime and he slept poorly the previous night, but he thinks he can drive the five miles home to his house.

He plans to keep himself awake in his car by rolling down the window and playing loud music (increasing sensory input to prevent sleep). He dies instantly when his car hits a tree.

Dr John Faul is a respiratory physician and sleep specialist at the Hermitage Medical Clinic.
During the Sleep Challenge he will be providing practical input on how people can improve their sleep.