In the last few weeks, it’s highly likely you’ll have seen in the news and on social media, lots of suggestions on ways to support your immune system. Whilst this is well intentioned, these myriad recommendations, some of which are impossible to implement with current food shortages, could have left you feeling confused and overwhelmed.
You may have even felt prompted to buy immune supporting supplements. Or maybe you’ve increased how many fruits and vegetables you’re eating, which, supply permitting, is definitely a good idea…….
However, did you know there’s something we can all do to support our immune system and overall wellbeing that’s available to us all, every day, and it’s totally free!
SLEEP!

In today’s Wellness Wednesday we will look at how a good night’s sleep can help you support your health and wellbeing ……. And I will then give you my top 10 strategies to help support improved sleep.
Let’s begin with a quick explanation of how your Immune System works.
Immune System 101
Our immune system is constantly on alert to identify and destroy anything that threatens to attack the body and cause illness, such as viruses, bacteria and infections. We are continually exposed to organisms that are inhaled, swallowed or inhabit our skin and mucous membranes. Whether or not these organisms lead to disease is decided by the integrity of our body’s immune system, and of course, our exposure. To function optimally, the immune system requires many nutrients, vitamins, minerals, relaxation, regular exercise and a good night’s sleep!
Once exposed to an infection, our body has a number of different ways of responding. I like to think of it like a military operation. Certain cells are responsible for the initial response, which is then followed up, by sending in highly trained specialist forces!
Our first line of defence against a virus comes from the Innate immune system who send in the foot soldiers. This system is a best described as “non-specific” and involves sending in Natural Killer (NK) cells.
In some cases, the foot soldiers (NK cells) may be enough to prevent a large-scale infection. However, if the infection proceeds beyond the first few rounds of viral replication, the Adaptive immune response, kicks into high gear.
Now we send in the “SAS”, a highly trained specific response to an understood threat.
The Adaptive immune response (SAS) has two battalions: virus-specific Antibody B cells. And virus specific T cells that kill infected cells.
The SAS are also involved in producing “memory cells” which is how we develop immunity to a subsequent infection from the same virus. As such the SAS can immediately recognise and respond to a second invasion.
(NB. Unfortunately often times viruses mutate, making the SAS response less effective!)
WHY IS SLEEP SO IMPORTANT?
From an evolutionary perspective sleep seems to be at odds with our survival!
During this potentially dangerous prolonged period of semi-consciousness, we could not hunt, gather food, procreate, protect ourselves or our young. Yet despite this, we continued to evolve needing sleep….and crazily we spend approximately a third of our lives in this semi-conscious state!
The amazing thing about Sleep is that it offers us a multitude of health benefits and is free at the point of service, every 24 hours!
But SLEEP is by no means a passive condition.
Whilst asleep, our bodies are highly active and perform many vital “housekeeping” jobs which allow us to remain healthy. Here’s a few of the tasks we get up to whilst horizontal!
- Muscles and joints -are rebuilt with the release of Growth hormone. The more sleep you get the better equipped your body will be to repair itself. In fact, the better you sleep, the better you can train and exercise. Did you know that if you train after a poor night’s sleep you are more likely to get injured and you will actually breakdown more muscle in the process?
- Heart – Our heart rate slows down during REM sleep, giving it a period of relative rest and also allowing for a period of reduced blood pressure.
- Brain – Improves cognition, memory and learning. It shrinks 60% during sleep deep sleep, facilitating the flow of cerebral spinal fluid. This allows the glymphatic system to remove unhealthy, old cells and waste substances. It’s like putting the dishwasher on at night!
Clever stuff don’t you think! And all while your hopefully fast asleep! But what happens when we don’t get enough zzzzzz?
Impaired sleep has been shown to:
Reduce the number of foot soldiers (NK cells) and also affects their ability to communicate with one another, with other battalions (other immune cells and immune cell messengers) and also to send messages to the SAS!
Reduces the effectiveness of the SAS, (B-cells and T-cells) and results in lower numbers.
Increases the likelihood of infection and infection duration, and can have adverse effects on the genes that control your circadian rhythm.
Increases levels of other pro-inflammatory markers and this can lead to the onset of a number of long-term chronic health conditions.
Alter levels of the two hunger hormones responsible for appetite and satiety, Leptin and Ghrelin. So not only do you feel hungrier, it will also affect your ability to feel full! A double whammy for potential unwanted weight gain!
A final note about stress and sleep!

Prehistoric man (or woman!) evolved with a stress response designed for running away from tigers. You either escaped unharmed or were attacked and eaten! Physiologically, your immune system was primed, with foot soldiers readied, to heal wounds and infection. Whilst this was extremely stressful on our bodies…it was thankfully over relatively quickly.
In our modern world, we may not have to worry about marauding tigers. Instead, we now experience stress that is ongoing, and in these current unprecedented times, this stress can sometimes feel overwhelming. The stress hormone cortisol is produced in response to this and should follow a diurnal pattern, rising within 30 minutes of waking, then dropping throughout the day, reaching its lowest pint at bedtime. However, in periods of high stress, this pattern can become disrupted, which will then affect your circadian rhythm, decreasing short-wave sleep, increasing periods of light sleep and causing more frequent waking. High levels of stress hormones can also deplete the immune system.
And now for the solutions!
10 tips to improve sleep quality and duration.
- Let’s talk about caffeine. Did you know that after oil, caffeine is the second most traded commodity? These days, caffeine consumption is so integral to everyday life and socialising that it’s easy to forget that it’s actually a psychoactive drug! So try to avoid caffeine after midday and to limit your intake to 2 caffeinated drinks per day. Caffeine has a ½ life of 5-7 hours. That’s how long it stays in circulation and can affect your sleep.
- Try to avoid any screens, your phone, i-pad, computer, at least one hour before bed and keep your bedroom as dark as possible. The onset of dusk brings about the production of melatonin, the sleep hormone. Research has shown that artificial light impairs its production and may be responsible for difficulties getting to sleep. A recent study showed that reading a book on an i-pad at bedtime reduced the production of melatonin by over 50% compared to reading from a real paper book. Worth considering when reading to your children at bedtime.
- Balance your blood sugar throughout the day: swings and dips can make you wake up in the night or earlier than normal. (For a more detailed explanation go to my Facebook page and search “Blood Glucose”)
- Aim for approx. 7- 8 hours sleep per night. Studies found that those who slept less than six hours a night were over four times more likely to get a cold than adults who slept more than seven hours.
- Rethink that drink! Sorry Guys…. To quote a leading sleep researcher, Matthew Walker, from his bestselling book “Why We Sleep”
“Alcohol is a sedative and sedation is not the same as a good night’s sleep”.
One glass can affect sleep quality and will also down regulate your immune system.
- Stick to a regular time for both going to bed and waking up. Be careful about weekend lie-ins too…Having a lie-in of more than an hour can have the same effect on the body as jet lag.
- Keep your bedroom cool. To successfully drop off to sleep, your core body temperature needs to decrease 2-3 degrees Fahrenheit (1-degree C). This drop also helps trigger the production of melatonin. Aim for 17-18 degrees or lower.
- It may be wise to avoid watching the news an hour before bedtime. This will avoid the stress response which was discussed above.
- Have a cuddle before bedtime! A cuddle before going to sleep triggers your body to release chemicals that can help you de-compress after a stressful day. The magic chemical released is the hormone oxytocin (nicknamed the “cuddle chemical”). Not only will it aid sleep, it also relieves pain and stress, and even better….it can boost your immune system.
- Try listening to a meditation app before bed or practice some deep breathing. If you are feeling anxious at bedtime, this will help to reset your nervous system and improve your sleep quality. I particularly like the meditation called “Loving Kindness Meditation”. Here’s the link:
https://www.mindful.org/loving-kindness-meditation-cultivate-resilience/
Here’s hoping for a rested peace-filled blissful night of Sleep!

If you have any questions or would like further support or information about your sleep, your immune health, or have any other wellness or nutrition related queries then please feel free to email me: Kbrookhouse66@gmail.com
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Besedovsky, L., Lange, T. and Haack, M. (2019) The Sleep-Immune Crosstalk in Health and Disease Physiol Rev. Published online. doi: 10.1152/physrev.00010.2018
Dimitrov S, Lange T, Tieken S, et al. (2004) Sleep associated regulation of T helper 1/T helper 2 cytokine balance in humans. Brain Behav Immun. 18(4):341–348 https://www.sciencedirect.com/science/article/pii/S0889159103001442?via%3Dihub
Irwin, M., McClintick, J., Costlow, C. et al. (1996) Partial night sleep deprivation reduces natural killer and cellular immune responses in humans. Published Online
https://doi.org/10.1096/fasebj.10.5.8621064
Lyons, A. B., Moy, L., Moy, R., & Tung, R. (2019). Circadian Rhythm and the Skin: A Review of the Literature. The Journal of clinical and aesthetic dermatology, 12(9), 42–45 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6777699/
Walker, M. (2017) Why We Sleep Penguin Books