Wake up! Wake up! Wake up! The dangers of alarm clocks and waking up suddenly

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If we lined up all my ancestors and asked them to hold hands, starting with my dad and ending with the very first Homo Sapien Billington – one of the ones who first stood upright, chipped away at a stone and worked out how to start a fire and enjoy a lion steak – we’d have a line of about 7,500 people 9 km long. This ancestral line represents 150,000 years of existence. How many of us were woken up by alarm clocks? Three, maybe four, my great-granddad, granddad, dad and me. The other 7,496 woke up when the sun woke them up. That’s what our brains have evolved to expect and use. What has this really go to do with my ability to sleep better?

Light plays a fundamental role in regulating our body clock and sleep-wake cycle. As well as that it comes up nice and slowly and so wakes you up slowly. A gentle nudge that the day is starting to gently bring you out of sleep. Definitely different to the get up punch in the face an alarm clock delivers.

Are alarm clocks bad for you?

I’m sure we all have a feeling that being suddenly woken up by a piercing alarm can’t be good for you. And we’d be right. A study carried out by the National Institute of Industrial Health in Japan, found those who were suddenly forced awake had higher blood pressure and heart rate than those allowed to wake naturally.

Mornings are high-risk times for strokes and heart attacks, the cause being the natural rise in blood pressure as we wake up. But if we’re given an unnatural and sudden shock it may shock our cardiovascular system and increase the risk of heart attacks. Monday mornings are usually the day with the highest number of heart attacks. This is perhaps due to sudden shock of an early and unnatural wake up after getting used to a more natural and slower waking up over the weekend.

During the early morning and the later stages of your sleep fluctuations in your blood pressure, heart rate and breathing are more extreme than usual as you regulate your body less. Also, your blood thickens because you are lying relatively still. These are not good conditions to be suddenly woken up in. The sudden noise of an alarm clock can trigger the fight or flight response filling you with adrenaline and other stress hormones. Then there is the actual act of getting up often results in a huge surge in blood pressure to get going. All these things combined could be a recipe for a heart attack. There is evidence that if a morning routine like this continues for weeks or months it can lead to chronic stress.

In March in England clocks go forward for daylight saving time. We’re all woken up an hour early and get an hour less in bed. Annoying as it is, there is a more serious side to this. A 2014 article in journal Open Heart reported a 24% increase in heart attacks the Monday following the clocks going forward compared to the weeks surrounding the start of daylight saving time. The exact reasons aren’t know but there are several ideas including the sudden disruption to circadian rhythm and shock inducing stress.

So how else do I wake up?

Routine is a powerful thing. The more of a routine you keep the stronger your circadian rhythm and the more you’ll be ready to wake up. Having a routine and getting lots of natural light to regulate your sleep-wake cycle will take the shock out of being woken up.
Natural light. Keeping your curtains a little open and allowing natural light to creep in will gently bring you out of sleep. Owing to very different lengths of day throughout the year, this of course is an option for few of us or an option only for a few months of the year. It does work though.

Sunrise alarms. There are a range of natural light simulators on the market. These work like alarm clocks but instead of sound or as well as sound they light up, usually gradually over 30 minutes or so. I bought one of these a few months ago. It’s been life changing. Every morning I’m gently brought out of sleep. When the sound part of the alarm starts I’m already half awake and not the least bit shocked out of sleep.

Increasing volume of alarm clocks. Many alarms offer this feature, it’s easy and will help to make waking up less of a shock. It’s better than a sudden shock, that’s for sure.
And a last thought. Be prepared. If you have to get up unusually early or perhaps the clocks are moving forward start waking yourself up a little earlier each night for 3 or four nights in advance. This will certainly reduce the shock of being woken up. This is something to think about if you are in an ‘at risk’ group for having a heart attack.

Written by
Sam Billington

Sam is our sleep guru. I am fascinated by sleep and I've used my science training to research and learn about sleep. I have been providing sleep advice and personal sleep plans for years. My day job is Head of Workplace Culture in Defra, I live in London with my wife and have a PhD in Ecology and Biology.