Arguably one of the lesser-known effects of sleep deprivation: it can lead to periodontitis, which is a serious gum infection that damages the soft tissue and can destroy the jawbone (*shivers*). A study conducted by The Osaka University Graduate School of Medicine found that individuals who got less than seven hours of sleep per night were at higher risk for this oral condition. Sleep deprivation affects oral health because it can trigger increased gum inflammation and end up seriously hurting your smile. Protect your teeth — get good sleep.

Unfortunately, a number of the effects of sleep deprivation can lead to acne breakouts. When you're running on very little sleep, your immune system weakens and makes you more vulnerable to acne-causing bacteria. The increased inflammation that comes with sleep loss can also get in the way of clear skin, turning small pimples into angry, red ones. Additionally, skipping out on rest can cause stress that leads to a cortisol increase in the body — which in turn triggers your skin to produce more sebum, and more acne.

According to the Belgravia Centre, a leading hair loss clinic, hair loss and sleep deprivation have a connection. Since the lack of sleep is a form of stress and such strain leads to hair loss, consequences include temporary hair loss conditions (like the stress-triggered telogen effluvium) and worsening of hereditary hair loss in people with a family history of male or female pattern hair loss. This just goes to show that even the smallest things, like getting a few extra hours of sleep every night, can help keep your hair and body healthy.

Many of us have seen or dealt with this one before (cue the dreaded "are you feeling okay, you look sick" that you get from people who notice your tired eyes after an all-nighter). Dark circles commonly arise when you don't get a good night's sleep because blood vessels will dilate under the delicate skin near your eyes, creating the dark, shadowy appearance. Lack of sleep can also cause puffiness in this area, when fluids seep into the skin and cause swelling.

A study from the research journal Sleep found that sleep-deprived individuals are more prone to hanging eyelids, droopy corners of the mouth, and an all around increase in wrinkles and fine lines on the skin. This happens because consistent loss of sleep contributes to reduced collagen formation — making your skin age prematurely. In fact, when UK researchers examined 30 women who slept six hours a night for five nights (switching from an eight-hour-per-night routine), they found that the participants had double the amount of wrinkles and fine lines on their faces. Before you splurge on a product, get a few nights with solid rest and you'll likely feel a whole lot fresher.

Sleep deprivation suppresses the function of the immune system. Though you may not notice it, not getting enough sleep may begin to decrease your body's ability to fight off colds and bacterial infections — and there's nothing worse than being tired and sick. Not to mention, sleep loss can increase the risk of fever. Often, fevers rise at night time, so losing hours of rest only worsens the effect of the illness.