Sleep, while one of the most blissful and relaxing things we do to survive, is also one of the most essential. When we close our eyes for those few hours each night, we give our body the chance to recharge after all the previous day’s stresses. Millions of processes go on while you sleep, helping the brain commit things to memory while cells go to work regenerating and repairing the damaged tissue from while we were awake.
When we don’t sleep, however, none of this can happen. Not only will we awake feeling cranky the next day and have difficulty concentrating, but prolonged periods of sleep deprivation may seriously affect our health. In fact, ample research has been conducted on what happens to different body parts if we are not getting our eight hours each night.
These studies have found that lack of sleep can cause several serious and life-threatening conditions, ranging from cancers to diabetes and heart issues. So, what exactly are the conditions that have been officially linked to poor sleeping habits? Click “view slideshow” to find out a few.
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A 2013 study conducted by researchers at Johns Hopkins University found that a lack of sleep can contribute to Alzheimer’s disease and impact the speed of the disease’s progression.  The study was conducted based on previous research that discovered sleep is necessary for the brain to get rid of “cerebral waste,” or the garbage-like buildup that can accumulate and cause dementia.
Conducting their study on 70 adults between the ages of 53 and 91, researchers found that those who reported getting poor sleep each night showed a greater amount of beta-amyloid deposition in their brains on PET scans. This compound is known to be a definitive marker of Alzheimer’s disease, leading researchers to conclude that lack of sleep prevents the brain from getting rid of this form of “cerebral waste.”
2. Obesity and Diabetes
Diabetes has long been linked to poor sleep. A study conducted by researchers at the University of Chicago unpacked how poor sleep can potentially cause obesity and, ultimately, lead to diabetes.  Knowing that fatty acid levels within the blood can impact metabolism speed and insulin’s ability to regulate blood sugar, researchers examined the effects little sleep had on fatty acid buildup.
Examining 19 men’s sleeping patterns, researchers found that those who got only four hours of sleep over the span of three nights had high levels of fatty acid in their blood between 4 a.m. and 9 a.m. This was a 15 to 30 percent increase over those who got 8.5 hours of sleep each night. Also, researchers found that the increase in fatty acid levels caused a higher degree of insulin resistance, all signs they attribute to pre-diabetes. However, those who got more sleep did not present the same markers for obesity or pre-diabetes.
3. Cardiovascular Disease
Cardiovascular disease has been linked to poor sleep for some time. A study presented at EuroHeartCare, the annual meeting of the European Society of Cardiology, found greater evidence of a strong correlation.  After following 657 Russian men between the ages of 25 and 64 for 14 years, researchers found that nearly two-thirds of those who experienced a heart attack also had a sleep disorder.
Moreover, the men who complained of sleep disorders also had a 2.6 times higher risk of myocardial infarction, a heart attack that occurs when the heart muscle dies, and a 1.5 to four times greater risk of stroke.
It may be shocking, but research conducted in 2014 found a link between increased incidences of suicide in adults and poor sleep, regardless of past history with depression. During a 10-year study conducted by researchers at the Stanford University of Medicine, 420 participants ranging from middle to late adulthood were examined. Out of this group, 20 participants were found to suffer from poor sleep and, unfortunately, committed suicide.  Because of this, researchers concluded that those who were experiencing difficulties sleeping consistently were 1.4 times more likely to commit suicide.
Those who were more vulnerable to this effect of poor sleep, researchers say, were white males 85 years or older. The study ultimately attributed this increased rate of suicide to sleep deprivation associated with health problems and stress that increases with age.
5. Ulcerative colitis
Ulcerative colitis, an inflammatory bowel disease marked by ulcers within the lining of your digestive tract, and Crohn’s Disease can be a product of sleep deprivation and excess sleep, according to a 2014 study.  Researchers from Massachusetts General Hospital found that the right amount of sleep is necessary to curb inflammation responses within the digestive system, which often lead to the two diseases.
After studying women enrolled in the Nurses’ Health Study (NHS) I since 1976 and NHS II since 1989, researchers found that risks of ulcerative colitis increased as sleep per night decreased to six hours or less. Alternately, researchers also found that more than nine hours of sleep increased risks as well, suggesting that the threshold for stopping digestive inflammation is a very narrow window that requires just the right amount of shut-eye. Although this response was only found in adult women, the increased chances of developing ulcerative colitis when getting little sleep existed despite other factors like age, weight, and habits like smoking and drinking.
6. Prostate Cancer
In a 2013 study published in the journal Cancer Epidemiology, Biomarkers and Prevention, researchers found an increased incidence and severity of prostate cancer in patients with sleep issues.  After following 2,425 Icelandic men between the ages of 67 and 96 for three to seven years, researchers discovered that the danger of developing prostate cancer rose in 60 percent of men who had trouble falling asleep. This number doubled with men who reported having difficulty staying asleep. What’s more, those who experienced sleep problems were also more likely to have later stages of prostate cancer.
The study’s researchers attribute this link to melatonin, a hormone that regulates sleep. Higher levels of melatonin have been previously found to suppress tumor growth, while melatonin levels in those exposed to too much artificial light (a known cause of sleep deprivation) were found to have more aggressive tumor growth.
Keep Reading: 9 Reasons Why You Should Be Sleeping Naked, According to Science
- Spira AP, Gamaldo AA, An Y, et al. Self-reported Sleep and β-Amyloid Deposition in Community-Dwelling Older Adults. JAMA Neurology. 2013.
- “Shorter Sleep Duration And Poorer Sleep Quality Linked To Alzheimer’s Disease Biomarker”. John Hopkins Bloomberg School of Public Health. N.p., 2013. Web. 7 June 2017. Source
- Broussard, Josiane L. et al. “Sleep Restriction Increases Free Fatty Acids In Healthy Men”. Springer Link. N.p., 2015. Source
- Bernert, Rebecca A. et al. “Association Of Poor Subjective Sleep Quality With Risk For Death By Suicide During A 10-Year Period”. The JAMA Network. N.p., 2014. Web. Source
- Ananthakrishnan, Ashwin N. et al. “Sleep Duration Affects Risk For Ulcerative Colitis: A Prospective Cohort Study”. Clinical Gastroenterology and Hepatology. N.p., 2014. Web. Source
- Sigurdardottir, L. G. et al. “Sleep Disruption Among Older Men And Risk Of Prostate Cancer”. Cancer Epidemiology, Biomarkers & Prevention. N.p., 2013. Web. Source