Sleep 101: Essential Reading for Sleep Evangelists- By Dr Sophie Bostock
1. How much sleep do we need?
Sleep experts recommend that most adults need 7-9 hours sleep for optimal health. This is an average, and while this suits most people, there will be a minority who can thrive on less, and some who need a little bit more. You are the best judge of how much sleep you need to feel on top form. If you answer yes to more than two of the following questions, it might be worth experimenting with a little more sleep?
- Do you rely on an alarm clock to wake up?
- Do you need caffeine, naps or sugar to keep you going through the day?
- Do you find yourself snapping at other people, for very little reason?
- Do you fall asleep within 5 minutes of your head hitting the pillow?
- Do you lie in at the weekends (or rest days) to catch up?
2. What’s so great about sleep?
Sleep is essential for survival. In fact, we can survive for longer without food than without sleep. Sleep is an active process for repairing the brain and body, and enhancing performance. Driving a car after 19 hours without sleep will put your co-ordination and reaction time on a par with a drunk driver. In the longer term, insufficient and poor quality sleep has been linked to increased risks of diabetes, depression, obesity, high blood pressure, heart disease and early mortality. The most acute links between poor sleep and health are those with mental health; insomnia more than doubles the risk of future anxiety and depression. Positively, the relationship is bidirectional, so improving sleep actually
3. What makes you fall asleep?
Two independent processes control your sleep. Firstly, there is a sleep pressure which builds up gradually the longer you’ve been awake. Secondly, there’s your body clock. In fact, every cell in the body has its own molecular clock, programmed to operate on a 24 hour ‘circadian’ rhythm. Our body clocks are heavily influenced by light. When it gets dark, the brain produces melatonin, which signals to the body that it’s time for sleep.
4. Does lack of sleep make you fat?
Both short sleep and irregular sleep patterns have been linked to increased risks of weight gain. There are at least 4 reasons why this happens:
- Disruption to appetite hormones, so that you’re more likely to feel hungry, and less likely to feel full
- Disruption to dopamine reward circuits in the brain, so that you’re more likely to crave high fat, high calorie foods
- Disruption to self-control, so that you’re less likely to be able to resist cravings
- Disruption to metabolism, so that you’re more likely to store calories as fat.
A recent review found that people who slept between 3.5 and 5.5 hours per night consumed, on average, 385 calories more the next day compared to people who slept for between seven and 12 hours. That’s roughly the number of calories in a McDonald’s double cheeseburger.
5. What time should I stop drinking caffeine?
Caffeine temporarily masks sleep pressure. Excess caffeine means you can lose track of whether or not you’re getting enough sleep, and it can make sleep lighter. The more caffeine you drink over time, the more you build up a tolerance to its effects.
Because of the different speeds that people process caffeine, it’s hard to prescribe a specific time to stop using it, but it has been shown that drinking the equivalent of a double espresso, 6 hours before bed, can reduce total sleep time by over 40 minutes, and double the time taken to fall asleep. If you’re struggling with sleep, try switching to decaf, especially after lunch.
6. Does the light from using screens before bed really interfere with your sleep?
Yes, it can do if the light is bright – but probably only if you’re exposed to it for 1.5 hours or more. But the sleep challenge is not just down to the light. If you use your phone or laptop before bed, you risk getting hooked on engaging content which – when your self-control is low before bed – means you displace sleep with scrolling. Online content, or work emails, also have potential evoke negative emotions, which could provoke a stress response and further delay melatonin onset.
If we delay the body’s natural rhythm of melatonin, we may end up falling asleep later, having a less restful night’s sleep and are more likely to feel groggy the next day. In children, access to phones at night, and screen time before bed have been linked to poor quality sleep and poor concentration at school.
7. I keep waking up at night. Do I have insomnia?
If you suffer from insomnia, you probably have a love-hate relationship with sleep; you would love to get more, and you really hate the fact you can’t.
According to the clinical criteria (DSM5), insomnia is defined as dissatisfaction with sleep, despite adequate opportunity to sleep, which interferes with normal daytime functioning, and is not caused by medication or another health condition. So you might have an issue with falling asleep, or staying asleep or waking up in the early hours, or just waking up feeling unrefreshed. The crucial part is that it messes with your day, as well as your night.
Simply waking up during the night is not necessarily a sign that you have a sleep problem.
8. Should I stop taking sleeping pills, or over-the-counter sleep aids?
If your doctor has prescribed you with sleeping pills, I’m sure it’s for a good reason, and it’s best to discuss your individual needs with them. Sleeping pills are not typically prescribed for more than a few weeks, due to the risks of tolerance, dependence and other harmful side effects. If you’ve been using them for a long time, ask your doctor about how to taper down your dose gradually.
If you’re having difficulty sleeping it can be incredibly frustrating, upsetting and isolating. It’s not unusual to look for a quick fix. Sometimes if you believe a product will be effective, it can reduce your anxiety about sleep and help you drift off; the so-called placebo effect. Many over-the-counter sleep remedies have little scientific evidence to justify that they are more effective than a placebo, so before you spend a lot of money, it’s worth checking the small print to see what research has been conducted to prove that they are effective, and who for.
9. How can I get back to sleep?
The biggest obstacles to falling asleep are often trying too hard, or worrying what will happen if you don’t. Your body wants to sleep, you simply need to let sleep come to you.
If you feel wide awake, lying in bed is a good time to practice meditation, or an imagery exercise. Crucially, if you can’t sleep for more than 20 minutes or so, don’t wrestle with it. Ideally get up, read a book until you feel sleepy, and only then go back to bed.
10. Can you summarise your top tips for improving your sleep, a.k.a R.E.S.T.?
- Routine: Stick to routine wake times, as often as you can
When we stick to the same wake up time and bedtime, our body clocks are more likely to hum along in synchrony. Haphazard routines, or night shifts, put more pressure on bodily functions, and mean the brain is less prepared for sleep. If a standard bedtime is a struggle, aim for waking up at the same time within an hour, 7 days a week. If this is not possible, aim for #2.
- Energise strategically by actively managing your Zeitgebers… light, exercise and food
A good blast of bright light in the morning helps us feel alert, whereas dimming the lights after sunset triggers the release of the hormone melatonin, which signals the brain that it’s time for sleep. Exercise helps pep us up, and has the added benefit of aiding deep sleep at night. Food also sends a wake-up signal, so finish eating at least two hours before bed.
- Switch off from stress: wind down before bed
Parents know that a consistent bedtime routine is essential for their hyperactive toddlers, but it’s good news for adults too. Give yourself an hour to unwind – that means no more work, no phone and no bright lights. If stress is the issue, and your mind won’t stop racing, put a piece of paper and a pencil by your bed. Before you get into bed, spend 10 minutes writing down what’s on your mind. If those thoughts pop up, tell yourself they’re on the page, and let them go.
- Temperature. Your sleep environment? Think luxury cave. Dark, quiet and cool – about 18C. A drop in body temperature is a cue for sleep. Taking a warm bath or shower 1-2 hours before bed can aid sleep – not only does warm water help your muscles to relax, the cooling that takes place as you exit the bath could help to induce a restful slumber.