Sleep and the Immune System

March 15, 2020 3 min read

Sleep and the Immune System


Sleep and the Immune System


Most of us are well aware of the effects of a good night’s sleep on your complexion. But did you know that lack of sleep can negatively affect your immune system?

Studies show that people who don't get quality sleep or enough sleep are more likely to get sick after being exposed to a virus, such as a common cold virus or influenza. Matthew Walker is a leading sleep scientist, director of the Center for Human Sleep Science at the University of California and author of the best-selling book Why We Sleep. He believes if we reduce sleep even for a single night, resilience to bacterial and viral infections is hindered.

Lack of sleep can also negatively affect recovery time and efficiency if you do fall ill. As we sleep, the immune system releases proteins called cytokines. Certain cytokines need to increase with infection or inflammation, and particularly when you're under stress. Sleep deprivation may decrease production of these protective cytokines. In addition, infection-fighting antibodies and cells are reduced during periods when you don't get enough sleep.

In short, your body needs sleep to fight infectious diseases.


 

Adequate Sleep and Sleep Quality

Just how much sleep is required to booster your immune system? The recommended sleep time is at least 7-9 hours for healthy adults. Any more, and the benefits begin to taper off.

Mathew Walker recommends the following to maximise your sleep and sleep quality -


Stick to a sleep schedule

Aim to go to bed and wake up at the same time each day - this applies to the weekend too. Unfortunately, a sleep-in does not make up for missed sleep earlier in the week. It can be a good idea to set a reminder or alarm for bedtime.

Don’t exercise too late in the day

Exercise has been shown to aid sleep quality, and we should all aim to get at least 30 mins each day. However, this should be no later than 2-3 hours prior to bed.

 
Avoid caffeine & nicotine 

Sodas, coffee, teas (that aren’t herbal) and chocolate all contain the stimulant caffeine. Try to avoid consuming after midday – even your afternoon coffee can have a significant impact on sleep. Nicotine is also a mild stimulant, and smokers will often wake up earlier than they would otherwise, due to nicotine withdrawal.


Avoid alcoholic drinks before bed

Alcohol may give the impression of a deeper sleep, but its presence severely hinders the quality of sleep. Alcohol has a habit of putting you in a state similar to that induced by sedatives - REM sleep is reduced, and you tend to stay in the lighter stages of sleep.

 
Avoid large meals and beverages late at night

If needed, a light snack before bed is OK, however large meals can cause digestive issues, that interfere with sleep. Drinking too much fluid before bed can cause you to wake during the night to urinate. 


Avoid medicines that delay or disrupt your sleep (where possible)

Some commonly prescribed heart, blood pressure or asthma medications, as well as some over the counter and herbal medicines for coughs colds or allergies can disrupt sleep patterns. Speak to your doctor, pharmacist or health-care professional as it may be possible to take them earlier in the day.

 
Don’t nap after 3pm

Naps are great, but taking them too late in the day can make it hard to fall asleep at night.

 
Make sure to leave time to relax before bed 

It’s important to have time before bed to unwind. Try to schedule your days so that there is time to relax before bed.

 
Take a hot bath (or cold shower) before bed

The reduction in body temperature after a bath may help you to feel sleepy; and the bath can help you to slow down and relax before bed. Paradoxically, a cold shower one hour before bed has the same effect!

 
Have a dark, cool (in temperature), gadget free bedroom 

Prioritise your bedroom for sex and sleep only. We sleep better at night if the temperature in the room is kept on the cool side. Gadgets such as televisions, mobile phones and computers can be a distraction, and the blue-light emitted reduces melatonin production, disrupting your circadian cycle. Attempt to black out the room completely - that might mean taping over any devices throwing unnecessary light.