Good sleep is essential for optimal health. We all know how bad we feel after a late night or one spent tossing and turning. Sleep is vital for regeneration of all aspects of our bodies and during sleep the body clears out the waste products from the day’s activities – especially in the brain. Although one night of poor sleep is not harmful, continued lack of sleep or poor-quality sleep can influence our health in many ways.
Sleep deprivation has been implicated in the development of several health conditions, including obesity, heart problems, type 2 diabetes, depression and Alzheimer’s disease.
Lack of sleep can affect our ability to drive safely in the same way as alcohol, with our reaction time to hazards being slowed to 4 seconds or more.
Of particular relevance at the moment, lack of sleep causes an increase in the stress hormone, cortisol, which in turn raises our blood sugar levels and both of these can make us more susceptible to infection and increase inflammation in the body.
The sleep hormone, melatonin, as well as controlling when we fall asleep, is also involved in the immune system as it is one of our body’s natural antioxidants. If melatonin levels are low, our sleep as well as our immune system will likely be compromised.
Lack of sleep makes us less able to cope with the stresses of daily life, being more likely to be short-tempered.
When we’re tired, food cravings are more likely and decision-making is less effective so junk foods become a lot harder to resist.
Sleep, it turns out, is so very important that Matthew Walker, sleep researcher and best-selling author of, Why We Sleep, asks rather “why do we wake up?”
How much sleep?
There has been considerable debate as to how much sleep we need, with some saying 8 hours is essential, others that 6 is sufficient. However, there is some research showing that if you’re routinely getting fewer than 6 hours, or are waking frequently it can adversely affect your health. Signs that you are getting plenty of good quality sleep are:
Waking up feeling refreshed and ready to take on the day
Waking up at around the same time every day without the need for an alarm
Being able to drop off to sleep within 30 minutes of trying
If these statements don’t apply to you, then you really should try to improve your sleep.
Top tips for good sleep
Aim to have a regular sleep habit: go to bed and get up at the same time each day – even at weekends! The regularity of this habit sets our body clock so that we are ready to fall asleep at the right time. Contrary to popular culture, having a lie-in does not pay back any “sleep debt” from previous short nights. Give yourself an 8-hour “sleep opportunity” which is to say that you are in bed long enough to get 8 hours…whether or not you actually do sleep for that long. Create a bedtime routine to help you wind down.
Get outside (without wearing sunglasses) during the morning hours, for at least 10 minutes every day, preferably 30 minutes or more. Even on a cloudy day the natural daylight will be much brighter than indoor light and will keep our body clock on time. In addition, exposure to sunlight (at least in the summer) increases vitamin D which in is needed in the biochemical pathway which creates melatonin.
Avoid caffeine from the early afternoon onwards. Caffeine blocks another one of the hormones that controls sleep. For some people who are particularly sensitive, the effects of caffeine on sleep can last 12 hours.
Don’t eat a heavy meal just before sleep: leave 3 hours between eating and bedtime.
Try exercising earlier in the day – not too close to bedtime, but do exercise: a daily walk has been shown to improve sleep. Ideally, don’t exercise after about 6.30pm. Light yoga-type exercise is fine however.
Don’t be tempted to use alcohol as a sleep aid: evidence shows sleep quality tends to be worse even if you fall asleep quicker after alcohol
Light blocks melatonin production. Therefore, make sure your bedroom is dark; use blackout lining or blinds and don’t use white night lights (red ones are OK) or have an illuminated alarm clock display (even a red display is not ideal if you tend to “clock watch” at night…not looking at the time if you wake at night does not help). Even those small LED lights that indicate something is charging or on stand-by can be enough to switch off melatonin. It can be beneficial also, to avoid bright lights in your bed-time routine. Often, we feel tired and ready for bed, then go to the bathroom to brush teeth etc and switch on the bright bathroom light just destroying the melatonin build up that was preparing the body for sleep! One tip is to do as much preparation for bed as possible earlier in the evening…change into pyjamas, brush your teeth etc. Then try to keep the lights low during the final bedtime run up.
Make sure your bedroom is cool. As our bodies cool down, this is another trigger for sleep, thus if your room is too warm, it may stop you from sleeping.
Avoid screen-based activities (phones, computer or TV) for at least an hour before you go to bed. The blue light from screens blocks melatonin production as well as keeping our brains fizzing. Avoid watching TV or using screens in the bedroom.
If you have to use screens, consider using apps to reduce the blue light and increase the red. Our bodies’ natural circadian rhythms take their cues from the light around us with blue light making us alert. These days most smartphones have in-built settings or apps that will reduce the blue light in the evening, or there are a variety of apps in the App Store/Google Play (see below).
Similarly, if you can choose the colour balance of your lights in the evening, aim for a reddish hue, and/or keep light levels low. Red light does not adversely affect melatonin – perhaps because we evolved to light our evenings with firelight!
Don’t use the bedroom for work, hobbies or anything that involves being too mentally active.
Try some meditation techniques (see useful info below). If anxiety or a busy brain is keeping you from sleeping, meditation or similarly calming activities before bed will help. Often, our brains are busy planning what we have to do tomorrow and ruminating on what we had done (or failed to do) today. One way around this is to keep a to do list and plan your activities. Once you have downloaded those worries to a piece of paper or an app in your phone, your brain can focus on sleep instead.
Check your mattress; seriously, try other types and invest in a new one if yours is ancient. You spend a third of your life on it; make sure it’s comfortable!
Focus on foods that are sources of nutrients that have been shown to be helpful for good sleep, such as: vitamin D (from sunlight and oily fish), vitamin C (good sources include peppers, green leafy vegetables, brussels sprouts and strawberries), vitamin B6 (almonds, avocados, fish, tomatoes, spinach, yogurt and eggs), magnesium (dark leafy greens and are some of the richest sources of dietary magnesium, but it is also found in avocados, pumpkin seeds, almonds, brazil nuts, pecans and macadamia nuts), potassium (found in leafy greens, broccoli, crimini mushrooms, and avocados), selenium (2 brazil nuts supplies your daily needs), sources of the amino acid, tryptophan which is needed to make melatonin (found in, for example, turkey, chicken, eggs, hemp seeds, almonds, cheeses and yogurt) and choline (found mainly in animal foods such as liver, eggs, fish and shellfish, but also in cauliflower, mushrooms, dark leafy greens,, asparagus, and brussels sprouts). All these nutrient-rich foods have benefits beyond improving sleep.
To nap or not to nap?
An afternoon nap is a tradition in many countries and may have health benefits. On the other hand, if napping is preventing you sleeping at night, then it would be advisable not to nap. Napping later in the day (such as dozing off in front of the TV in the evening) is more likely to affect night-time sleep than a nap after lunch.
Useful info
Apps to reduce blue light: fLux, Night Shift, Night Mode, Twilight, Bluelight Filter, Night Owl, Iris
Meditation apps to help sleep: Headspace, Sleepio, Calm, Slumber, Simple Habit, Insight Timer, 10% happier
Why We Sleep by Matthew Walker, 2017
You don’t necessarily have to do all of these things in order to have good sleep. Pick one or two new habits to implement now and I hope you can, armed with this information, improve your sleep and by so doing, support your health and immune system.
Now, what would you like me to cover next? I’d love to hear from you, with your pressing questions. And, of course, for more tailored nutrition and lifestyle advice, please get in touch to arrange an online consultation.