Good quality, restorative sleep is also crucial for the nightly cellular repair, regeneration and immune function. Every night, we go through repeated cycles of two distinctly different sleep phases: Rapid Eye Movement (REM, when the most active dreaming happens) and non-REM sleep (NREM, the deeper sleep). During NREM, blood flow is directed from our brain and body core, more towards the body’s periphery including the skin. Thus, a restorative hormone flow is established, and cellular repair is enhanced.
Sleep deprivation on the other hand is known to contribute to systemic inflammation, even after a short period of only a couple of weeks, as research has shown. In fact, sleep deprivation is thought to increase all sorts of age-related processes as well as chronic health problems.
At night we naturally release the ‘sleep hormone’ melatonin. Melatonin levels start to rise in the evening and peak around midnight before slowly subsiding again. This diurnal sleep-wake cycle is governed by the changes of light and darkness. If we don’t get enough sleep, our melatonin levels are impaired.
Interestingly, melatonin also helps protect our skin from the sun’s damaging effects and counteracts mitochondrial and DNA damage. Unfortunately, like so many other skin-friendly hormones, our melatonin level declines with age. Sleep deprivation will only hasten this natural decline.
Sleep deprivation is also known to impair insulin sensitivity and glucose tolerance and is connected to the development of diabetes. With regards to the skin, higher blood sugar levels mean higher generation of Advanced Glycation End products (AGEs), which again accelerate the skin’s ageing process.
Sleep is even connected to telomere length. Shorter telomeres have been associated with poorer sleep quality in women and shorter sleep in men. And in a fascinating genomic study, it was shown that sleep debt of only two nights led to a change in the expression of 500 genes. These changes were notably related to DNA damage and repair as well as stress and diverse immune system responses.
Sufficient sleep is also important for the nightly peak of our natural anti-aging hormone GH (growth hormone). This not only helps us look younger, but also helps to repair tissue. However, when we don’t get enough sleep, our natural GH level is sub-optimal – and this gets worse as we get older. Our skin cells regenerate more quickly at night. Collagen, the protein responsible for helping your skin keep its volume and elasticity, is produced as the skin cells regenerate
A study looking at the connection between sleep and longevity characterised the sleep patterns of people with a high life span (85 to 105 year olds) and compared these to other groups. The outcome confirmed the importance of maintaining strictly regular sleep-wake schedules.
Study - Human longevity is associated with regular sleep patterns, maintenance of slow wave sleep, and favourable lipid profile.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4067693/
