When you are blissfully slumbering, you may think that you are doing nothing and that your body is at rest. But nothing could be further from the truth. While you’re off in la-la-land, your body is actually kicking into high gear and performing all kinds of magic to help you stay healthy.

 

Let’s take a look at all the hard work that takes place while you’re totally oblivious. (Don’t worry, your body’s got this.)

Your immune system pulls an all-nighter.

Your immune system works by sending specialized T-cells on the attack to seek out and kill harmful viruses and bacteria. Removing these harmful organisms efficiently is what keeps you from getting really sick.

Your immune system works most efficiently while you’re asleep, because all of your body’s resources can go into fighting any infection. This includes your body’s ability to raise your core temperature and trigger a fever. Though uncomfortable, fevers help your immune system fight off infections, and your body is best able to heat up while you’re asleep.

When you don’t get enough sleep, your immune system suffers because your T-cells go down, and inflammatory cytokines go up, leaving you at greater risk of developing a cold or flu.

Your growth hormones put it in overdrive.

While you sleep, your body releases growth hormones that stimulate your tissues to regenerate and repair themselves. This means your muscles heal from injuries, and your skin is rejuvenated. When you don’t get enough sleep, the levels of these hormones dip and impede cellular growth.

Your weight loss hormones do heavy lifting.

As you catch some shut-eye, your body produces hormones that can affect your weight.

Research conducted at the University of Wisconsin found that people who get enough high-quality sleep have lower levels of ghrelin, a hormone that stimulates hunger and makes you crave junk food. The study also showed that people who get a good night’s sleep had increased levels of leptin, the hormone that regulates energy and keeps your appetite from spiking.

So simply put, when you’re sleep deprived, you have too much of the hormone that tells you to eat, and not enough of the hormone that tells you you’re full.

As if that isn’t bad enough, not getting enough sleep can affect certain brain receptors that control motivation and your brain’s reward system. Researchers found that if you’re sleep deprived, your hedonic drive for certain foods gets stronger, and your ability to resist them may be impaired. So you are more likely to give in to temptation.

Your brain works overtime.

While you’re catching zzz’s, your brain is sorting through the day’s memories, choosing what to keep and what to discard. The “keepers” are then connected with related information. If consolidation doesn’t happen, you aren’t able to recall new facts. That’s why pulling an all-nighter to cram for an exam is rarely a good idea – you aren’t giving your brain a break in which to process and categorize what you’re learning.

Not getting enough sleep has also been linked with an increase in the buildup of beta-amyloid in the brain, a toxic plaque believed to cause Alzheimer’s. It appears that the brain “detoxifies” during deep sleep, so these toxins can build up and cause damage in those not getting quality sleep.

So, the next time you wake up feeling guilty for sleeping instead of being productive and getting more work done, give yourself a break. Your body’s been working so hard during the night, that you almost deserve to go back to sleep.