Suprachiasmatic Nucleus (what?)

Written By Lynn McCardle

The first time I heard of this nucleus I started singing Mary Poppins’ Supercalifragilisticexpialidocious!

Although it seems like a nonsensical, made-up word, it is actually just as great and extraordinary as the Mary Poppins word. This nucleus manages our sleep, it’s our internal clock, you might know it as the circadian rhythm (1).

I love sleep, I love my bed, I love being warm and toasty and comfortable and, well, sleeping. I guard it ferociously. Which is why I love this nucleus.

Why, as a nutritionist, am I obsessed with sleep?

When we sleep our body repairs itself, it takes out the (metabolic) rubbish from our brain we’ve accumulated during the day, when it’s busy concentrating on keeping us walking, talking and breathing. Accumulating this rubbish leads to our brains not functioning optimally - hello brain fog, memory problems, random forgetfulness and dodgy decisions (2).

When we don’t sleep well our hunger hormones also take a hit. So when we wake up tired, we wake up hungry. Our ‘hunger hormone’ ghrelin (think gremlin ghrelin) is higher and as a result we eat more that day. Almost 400 calories more (3). And it’s not 400 extra calories of broccoli we crave, it’s the sugary, starchy foods such as chips and mars bars (4). A recent study also showed that participants who slept more, lost weight (5)

When ghrelin is increased so is the volume of fat deposited into our cells because it also stimulates insulin, so we tend to put on weight (6). Especially around our middle - aka muffin top.

As we eat more sugar and carbs, our blood glucose starts to go up, up, up. Then it comes crashing down, so we reach for more sugar, and on we go all day. Then we crash into bed exhausted at night.

Insulin increases when blood glucose goes up and, over time, this can lead to insulin resistance, pre-diabetes then type 2 diabetes (7).

So now you can see why I am obsessed with sleep. It keeps our bodies healthy, our brains functioning, our blood glucose and appetite regulated. And it makes me a lot less grumpy. So how can I get better sleep you ask? There are some tips below, but if you feel you need additional help with sleep or appetite or brain fog or any other symptoms I’ve mentioned, book an appointment with me to get your personalised plan.

Improved sleep tips

  • Finish eating 2-3 hours before bed to ensure you’re resting, not digesting, at bedtime.

  • Finalise your device use 1-2 hours before bed to ensure your brain doesn’t think it’s still daytime. Or invest in some good blue light blocking glasses.

  • Consume all caffeine before noon to ensure optimal sleep quality. Even if you sleep ok after caffeine, the science says your quality is impacted (another blog post maybe?!) and quality is key.

  • Leave devices charging outside your bedroom. If you use your phone as an alarm, buy a clock. NO excuses. Phones are sleep stealers.

  • The only thing your bedroom should be for is sleep and sex. No TV, no emails, no social media.

  • Make your bedroom as dark and quiet as possible.

  • And to help regulate that amazing nucleus, go outside in the morning, and get morning sun (even if it’s cloudy) so your body knows it’s morning and time to wake up!

  • Move as much as you can during the day. It doesn’t need to be a full HIIT work out, just a walk round the block after lunch or dinner will make a huge difference - and get you outside into daylight.

References

  1. Hastings, M.H., Maywood, E.S. & Brancaccio, M. (2108). Generation of circadian rhythms in the suprachiasmatic nucleus. Nature Review, Neuroscience, 19(8), 453 – 469. doi: 10.1038/s41583-018-0026-z.

  2. Eugene, A.R. & Masiak, J. (2015). The Neuroprotective Aspects of Sleep. MEDtube Science, 3(1), 35-40. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4651462/pdf/nihms734829.pdf

  3. Al Khatib, H.K., Harding, S.V., Darzi, J. & Pot, J.K. (2016). The effects of partial sleep deprivation on energy balance: A systematic review and meta-analysis. European Journal of Clinical Nutrition, 71(5), 614-624. Doi: 10.1038/ejcn.2016.201

  4. Greer, S.M., Goldstein, A.N. & Walker, M.P. (2013). The impact of sleep deprivation on food desire in the human brain. Nature Communications, 4 (2013), 2259 - 2278. doi: 10.1038/ncomms3259

  5. Tasali, E., Wroblewski, K., Kahn, E., Kilkus, J. & Scholeer, D.A. (2021). Effect of sleep extension on objectively assessed energy intake among adults with overweight in real-life settings: A randomized clinical trial. JAMA Internal Medicine, 182(4), 365-374. doi: 10.1001/jamainternmed.2021.8098.

  6. Pradhan, G., Samson, S.L. & Sun, Y. (2013). Ghrelin: much more than a hunger hormone. Current Opinion Clinical Nutrition Metabolic Care, 16(6), 619–624. doi:10.1097/MCO. 0b013e328365b9be.

  7. Freeman, A.M. & Pennings, N. (2023). Insulin resistance. NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health. Retrtieved from https://www.ncbi.nlm.nih.gov/books/NBK507839/?report=printable

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The information provided in this blog is for your personal or other non-commercial, educational purposes. It should not be considered as medical or professional advice. We recommend you consult with a GP or other healthcare professional before taking or omitting to take any action based on this blog. While the author uses best endeavours to provide accurate and true content, the author makes no guarantees or promises and assumes no liability regarding the accuracy, reliability or completeness of the information presented. The information, opinions, and recommendations presented in this blog are for general information only and any reliance on the information provided in this blog is done at your own risk.

 

Lynn McCardle