Sleep Deprivation: More Than Just Feeling Tired

Do you know that fuzzy feeling you get when you're sleep-deprived? Your brain feels sluggish, your body aches with fatigue, and you could fall asleep anywhere. In our fast-paced society, getting a full night's rest has become a common struggle. While you may think that a simple cup of coffee or an occasional energy drink will cure your tiredness, researchers are finding that sleep deprivation can have far more serious consequences on your body than you might think.

So, why do we sleep? Virtually every creature on earth sleeps, and it's a vital process for our continued survival. While sleep may be simply a time for our bodies to shut down, the reality couldn't be more different. There are two main ways in which we benefit from sleep: our physical health and our mental health.

While we sleep, our bodies take the time to repair and rejuvenate themselves. Human growth hormone is released, which allows muscles to grow, damages tissues to be replaced, and other hormones to be produced. Cells prepare themselves for the following day's activities. The brain uses this time to sift through all the information it has collected throughout the day and process it. It decides what's important and needs to be retained and what is irrelevant.

Furthermore, the brain performs physical repairs on itself as well. The neurons in the brain are refreshed and restored by two different types of glial cells. Microglia cells are responsible for removing neurons that have become old or worn out by a process known as phagocytosis, which means "devour" in Greek. The other type of glial cells, the astrocytes, alter the synapses which connect neurons to ensure that their structure is as efficient as possible.

But what happens if we don't get enough sleep? A study conducted in Italy looked at mammalian brains during sleep deprivation. They found stark similarities between what was going on. They noticed that in sleep-deprived brains, the glial cells were still functioning but in an elevated and seemingly uncontrolled way.

The researchers conducted experiments involving four test groups of mice. The first group acted as the control and was allowed to sleep normally. The second group was woken up from their sleep at regular intervals. The third group represented sleep deprivation and was kept awake for an extra eight hours, and the fourth group represented chronic sleep deprivation and was kept awake for five days in a row.

The researchers looked at the activity of the astrocyte cells. They saw activity in 5.7% of the synapses of the well-rested brains and 7.3% of the synapses in the spontaneously awake brains. But it was the sleep-deprived brains that surprised researchers the most. In these cells, the astrocytes had taken on a new role and started to behave like microglial cells, actually devouring the synapses instead of rewiring them. In the sleep-deprived brains, this was seen in 8.4% of the synapses, and in the chronically sleep-deprived brains, it was seen in 13.5% of them.

The researchers also noted that the synapses that tend to be involved were the largest and oldest ones. This isn't necessarily a bad thing in the short term. This process could help clean out harmful debris and remove worn-out connections to allow new ones to thrive. But in the long term, this is a problem because uncontrolled microbial activity has been linked to Alzheimer's and other degenerative brain conditions. This could explain why a lack of sleep seems to make people more vulnerable to these illnesses.

Beyond this, there are several other health issues that can arise if you don't get enough sleep.