If you’re anything like most people, you probably don’t get enough sleep. Whether it’s due to your busy schedule or just because you’re kind of a night owl, a couple of missed hours here and there can start to really add up to some serious sleep deprivation.

Sleep is essential for your body to function correctly. When you get enough sleep, you’re likely to feel the difference in your mood and energy levels. How much sleep that entails differs from person to person— but a good guideline to follow is to aim for seven to eight hours of sleep each night. If you fall far below that, you’re going to feel groggy and irritable. But feeling less tired isn’t the only reason you should get the sleep you need. Here are 15 things that happen to your body when you get enough sleep.

Getting enough sleep can actually help you lower your risk of getting sick. Cytokines are a type of protein that your body uses to target and fight infection. These compounds are actually produced and released while you sleep, helping to ward off sickness and protect against germs you may have come into contact with during the day.

Everything from genetics to your diet affects your diabetes risk. But you might not have realized that sleep makes an impact, too. According to a meta-analysis of studies published in the journal Diabetes Care, people who get enough sleep (seven to eight hours per night) have the lowest risk of diabetes.

A study published in the American Journal of Cardiology showed that people who sleep seven to eight hours a night have a lower risk of heart disease than those who sleep just a couple of hours less on average. So even getting six hours of sleep could cost you. Other research shows that too much sleep, in addition to too little, can also result in a higher risk.

When you’re tired, you probably get a little snippy. So it probably doesn’t come as much of a surprise that getting enough sleep will leave you feeling happier. A study published in the journal Sleep showed that people who were allowed just 4.5 hours of sleep a night for a week reported feeling more stressed, angry, sad, and mentally exhausted. Once they were allowed to sleep normally again, they reported a dramatic improvement in mood.

Sleep-deprivation messes with your mind at a cellular level. A study published in the journal Nature Medicine showed that lack of sleep interferes with your brain cells’ ability to communicate with each other. Another study showed that even partial sleep deprivation can result in a worsened attention span. Get enough sleep and you’ll be better able to focus.

Blood pressure can be managed in part by paying attention to your diet and limiting your consumption of sodium-rich foods. But food isn’t the only thing you should improve upon to prevent high blood pressure. According to a study published in the journal Chest, both insomnia and sleep deprivation are associated with hypertension. To lower your risk, make sure you’re getting enough sleep each night.

Your cholesterol is a measure of lipid levels in your blood. Some cholesterol is necessary for hormone regulation, the production of vitamin D, and other bodily functions. However, too much cholesterol can result in plaque buildup in the arteries, which could be dangerous. Eating certain healthy foods can help maintain healthy cholesterol levels, as can getting regular exercise. But sleep can also make an impact. Studies show that both too much and too little sleep can result in high levels of “bad” cholesterol (LDL) and low levels of “good” cholesterol (HDL).

Cortisol is a stress hormone released by your adrenal gland. It creates the “fight or flight” reaction to fear and stress, and is quite important. But too much cortisol can be dangerous. If your cortisol levels are out of whack, you can end up with health problems ranging from headaches to heart disease. A study published in the journal Sleep showed that sleep deprivation resulted in elevated cortisol levels the following evening. A night of adequate sleep, however, showed no such elevation.

Inflammation is the body’s natural response to an internal threat such as an allergen, virus, or toxin. It’s a crucial mechanism that actually helps keep you safe. However, chronic inflammation — inflammation that does not cease because the body constantly perceives a threat — can pose a serious health risk. Chronic inflammation can occur due to frequent consumption of inflammatory foods, high levels of stress, or pollution. Lack of sleep can also cause an inflammatory response according to some research. Getting the rest you need is crucial for keeping damaging inflammation at bay.

According to a review published by the American Psychological Society, there is over a decade of research behind the idea that memory is aided by getting enough sleep. Sleep may actually be the time during which long-term memories are created and stored. Sleeping the necessary number of hours can help improve your long-term memory and help you to retain memories.

Hunger is in part regulated by two hormones: ghrelin and leptin. Leptin signals to your brain that you’re full, and ghrelin signals your brain to eat more. Leptin is produced during sleep — potentially due to the fact that you need less energy while you sleep than you do during your active, waking hours. If you get enough sleep, you will produce the right amounts of leptin and receive balanced and expected signals of fullness from the hormone. Ghrelin is affected by sleep, as well. During sleep, levels of ghrelin decrease. If you don’t get enough sleep, you can end up with more ghrelin than normal — so getting enough sleep helps this hormone to balance out, as well.

Studies have shown that sleep deprivation can hinder muscle growth and cause loss of muscle mass. If you’re working out with the intention of building strength, lack of sleep can seriously hinder your progress. Help your body out by getting the recommended amount of sleep each night.

REM sleep is a stage of sleep characterized by rapid eye movement, dreaming, and body movement. It’s typically thought of as a stage of deep sleep, and may be more restful for the body than other stages. A study showed that after REM sleep, people showed an increase in creativity, whereas those deprived of REM sleep did not. So if you’re stuck in a creative rut, lack of sleep might be holding you back from a breakthrough!

A study of collegiate basketball players showed that after getting as much sleep as possible for six to seven weeks, athletic performance improved significantly. Whether you’re training for an event or just looking to feel more energized during exercise, getting the sleep you need can really help.

People who have trouble falling or staying asleep, or otherwise have chronic sleep deprivation, are at a greater risk for depression according to the National Sleep Foundation; so if you can get enough sleep, it might lower your risk. Many people have trouble falling asleep, even if they are able to get to bed on time. If that sounds like you, you might want to try adding a few of these calming rituals to your bedtime routine.

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This Is What Happens to Your Body When You Don’t Get Enough Sleep

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