Beyond the brain, disturbed sleep also has wider implications for our health.

For example, in diabetes – insulin resistance and hyperglycemia have both been linked with a decrease in this glymphatic, or waste-removal type, activity. Importantly, sleep problems such as insomnia, obstructive sleep apnea, short sleep duration, and shift work are associated with higher risk of type 2 diabetes (T2D) as well as worse prognosis. This suggests that it may be within our control to reduce risk factors of T2D associated with our lifestyles, for instance, by improving our sleep.

Moreover, it has been shown that being an evening type may also be associated with a greater risk of developing T2D (as well as arterial hypertension and a faster resting heart rate, as compared to morning types). If you identify yourself as an evening type – don’t worry – most people identify as one extreme or the other, but in reality most of us fall somewhere right in the (healthy) middle. All it sometimes takes is a shift in our sleep-wake patterns – which are very much within our control – to start to adopt more healthful sleep and waking habits.

Sleep may also have implications for the maintenance of our DNA. For example, recent research in Nature Communications showed that sleep may play an important role in reducing the accumulation of damage to single-cell DNA.

On the systemic level, a recent systematic review and meta-analysis showed that long sleep duration – so too much sleep – as well as sleep disturbance were both associated with an increase in key markers of systemic inflammation in the body. Of course, not all inflammation is bad. For example acute inflammation that occurs after an intense workout is usually beneficial for the body, and there may also be a case for the hormetic response (i.e., dose-dependant beneficial effects on the body). However, inflammation can become problematic when it reaches chronic or sustained levels.

Of course, we all probably have first-hand experience with the detrimental effects that poor, or lack of, sleep can have on our cognitive abilities – such as our memory or attention. In the short term, these faculties take a noticeable hit. In the longer term, poor sleep may have more sinister consequences and has been shown to have a complex, and potentially bidirectional, relationship with neurodegenerative disorders such as Alzheimer’s disease.

One reason sleep seems to have such important implications for our cognition and memory, is that sleep helps us process the flood of information we accumulate on a daily basis while we are awake. For certain types of memory or skill learning, sleep uniquely supports a process of memory strengthening (this is referred to as memory consolidation) and is thought to occur through neural processes of homeostasis at the synaptic level in the brain. These processes allow our brains to avoid saturation or overload, and to reorganise and rebalance so that we can be ready for learning new information the next day.

All in all, our sleep – and our brains at large – are rather remarkable at enabling us to go about our lives to the best of our abilities. For this, I think they deserve the occasional mad fanboy/fangirl standing ovation.