Sleep is one of life’s few universals. Most animals need shuteye in one form or another, from the frigatebirds that sleep in flight to the jellyfish that doze off under the sea. Why do we need to spend a third of our lives asleep? That’s one of the biggest lingering questions in science.
What we do know is that study after study has shown the consequences of not getting enough sleep.
From weight gains to reduced mental capacity, poor sleepers are at a higher risk of a wide range of health issues. If they persist for years, these problems can ultimately increase the risk of dying early. Fortunately, there are steps you can take to reduce the effects of sleep deprivation.
Can Lack of Sleep Make You Sick?
It’s happened to most of us: You stay out too late with friends or work through the night on deadline only to get sick soon after. Your body can’t fight off viruses or bacteria as easily if you’re not getting enough sleep.
While we dream, our immune systems are hard at work creating and releasing tiny proteins called cytokines. These minuscule messengers tell our immune system to ramp up or down its activity (Duque and Descoteaux 2014). And we now know that too little sleep can translate to reduced cytokine activity, which means you can’t fight off an invading illness as easily.
Other research has also found a lack of sleep might reduce the effectiveness of vaccines.
In a study published in the journal Sleep, 125 adults in Pennsylvania kept a journal tracking their nightly sleep patterns, while many also wore electronic sleep monitors. Then, researchers administered a standard three-dose hepatitis B vaccine and monitored each person over the course of more than six months to see if their immune system would effectively respond to the virus (Prather et al. 2012).
People who averaged less than six hours a night were nearly 12 times less likely to be protected by the vaccine.
The Benefits of Sleep for Skin
There’s even some science behind the concept of beauty sleep.
In a 2013 study published in the journal Sleep, Swedish researchers asked volunteers to look at pictures of people’s faces (Sundelin 2014). In one set of images, the subjects had gotten a full eight hours of sleep. In a second group of pictures, the same subjects were photographed after not sleeping for 31 hours.
Volunteers looking at the pictures said the sleep-deprived subjects had droopy mouths and eyelids with red eyes underlined by dark circles, as well as pale, wrinkly skin. They also looked sad, the participants said.
The problems are more than skin deep. Research published in 2016 studied how people’s bodies responded after a few nights of sleep deprivation (Carroll et al. 2016). The investigators found that even this short-term lack of sleep damaged cells and accelerated the processes of aging at a molecular level.
Additionally, when exposed to environmental stressors, poor sleepers fare worse, needing more time to recover from things like sunburns (Baron et al. 2013).
Sleep Deprivation and Type 2 Diabetes Prevention
Regularly losing sleep is a strong risk factor for developing type 2 diabetes, a disease that’s roughly doubled in the U.S. since 1990. Type 2 diabetes is a burden by itself, but the ailment also increases the risk of heart disease, the number one cause of death in America.
According to the National Sleep Foundation, when you eat while sleep-deprived, your body releases less insulin — a hormone that regulates blood sugar. At the same time, your body is also pumping out stress hormones like cortisol. That makes it harder to sleep and harder for the insulin to regulate your blood sugar.
The connection between lack of sleep and poor blood sugar control seems to be strongest among people getting just four to six hours of sleep per night, as well as those not getting enough restorative deep sleep.
Sleep Loss and Weight Gain
To add insult to injury, your stressed-out, sleep-deprived zombie self also now craves unhealthy foods packed with carbs and sugar. That’s because missing sleep raises levels of some key hunger hormones (Taheri et al. 2004). As a result, short sleepers often have a higher body mass index, or BMI.
Typically, these problems play out over many years. For example, when researchers followed nearly 70,000 nurses for 16 years, they found that those who regularly slept five hours or less per night gained 2.5 pounds more than those who slept adequately (Patel et al. 2006).
While that long-term gain is modest, in some situations, these changes can also play out astonishingly quickly. In a study published in 2013, scientists saw 16 people gain an average of roughly two pounds of weight after just one work week with reduced sleep (Markwald et al. 2013).
“Our findings suggest that increased food intake during insufficient sleep is a physiological adaptation to provide energy needed to sustain additional wakefulness,” the authors wrote. “Yet when food is easily accessible, intake surpasses that needed.”
Heart Disease and Inflammation
In recent years, heart disease has been America’s number one killer. The umbrella term includes a variety of conditions that narrow or block blood vessels and can cause heart attacks, chest pains and strokes.
Some studies have linked a lack of sleep with an increased risk of heart disease. One possible mechanism: tissue-damaging inflammation (Faraut et al. 2012). And over time, that can lead to heart disease.
Scientists are still exploring why the link between sleep deprivation and inflammation exists, but immune system alterations may play a role (Irwin et al. 2016).
Natural Ways to Sleep Better
Reducing screen time before bed is one easy step you can take. The blue light from electronic screens increases our alertness and makes it hard to fall asleep. Other basics include avoiding caffeine and going easy on alcohol, which makes us drowsy but hurts our ability to enter deep sleep.
And while health officials have given us a long list of things to avoid, research has also turned up a number of small dietary pleasures and sleeping tips that can make it easier to drift off.
Most people associate the amino acid tryptophan with Thanksgiving Day. It’s often blamed for making people sleepy after a long afternoon of eating. But tryptophan’s head-nodding effects aren’t just a convenient excuse for feeling lazy — the amino acid really can make you sleepy.
Like omega-3 fatty acids, the body can’t make tryptophan on its own, so we have to get it from our food. The body uses it to make serotonin, a precursor to melatonin, an important hormone for sleep.
And turkey is far from the only source of tryptophan. You’ll also find it in other forms of poultry, like chicken, as well as eggs and cheese. Seafood, including wild-caught salmon, is also a great source of tryptophan.
Direct sources of melatonin include a variety of fruits and vegetables, as well as grains, nuts and seeds.
Magnesium can offer another path to sleep through food. The mineral works to deactivate adrenaline and helps your body rest. You’ll find it in leafy greens like kale and spinach, as well as a number of other vegetables, plus fruits like bananas, raspberries and avocados. Salmon and mackerel are also rich sources of magnesium.
So, when stressful times push you toward a burger and French fries, consider a salad topped with a fillet of fish. You’ll feel better in the morning.
Effects of Sleep Quality on Skin Aging and Function. University Hospitals Case Medical Center. "Sleep deprivation linked to aging skin, study suggests." ScienceDaily. ScienceDaily, 23 July 2013
Carroll JE, Cole SW, Seeman TE, et al. Partial sleep deprivation activates the DNA damage response (DDR) and the senescence-associated secretory phenotype (SASP) in aged adult humans. Brain Behav Immun. 2016;51:223-9.
Centers for Disease Control and Prevention. National Center for Health Statistics. Leading Causes of Death. https://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm
Arango Duque G and Descoteaux A (2014) Macrophage cytokines: involvement in immunity and infectious diseases. Front. Immunol. 5:491. doi: 10.3389/fimmu.2014.00491
Goel N, Rao H, Durmer JS, Dinges DF. Neurocognitive consequences of sleep deprivation. Semin Neurol. 2009;29(4):320-39.
Irwin M, Olmstead R, Carroll J. Sleep Disturbance, Sleep Duration, and Inflammation: A Systematic Review and Meta-Analysis of Cohort Studies and Experimental Sleep Deprivation. Biological Psychiatry, 2016.
Martella, D., Casagrande, M. & Lupiáñez, J. Alerting, orienting and executive control: the effects of sleep deprivation on attentional networks. Exp Brain Res 210, 81–89 (2011). https://doi.org/10.1007/s00221-011-2605-3
Markwald RR, Melanson EL, Smith MR, et al. Impact of insufficient sleep on total daily energy expenditure, food intake, and weight gain. Proc Natl Acad Sci USA. 2013;110(14):5695-700.
Patel SR, Malhotra A, White DP, Gottlieb DJ, Hu FB. Association between reduced sleep and weight gain in women. Am J Epidemiol. 2006;164(10):947-54.
Aric A. Prather, Martica Hall, Jacqueline M. Fury, Diana C. Ross, Matthew F. Muldoon, Sheldon Cohen, Anna L. Marsland. Sleep and Antibody Response to Hepatitis B Vaccination. SLEEP, 2012; DOI: 10.5665/sleep.1990
The Nobel Prize in Physiology or Medicine 2013. https://www.nobelprize.org/prizes/medicine/2013/press-release/
Taheri S, Lin L, Austin D, Young T, Mignot E. Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index. PLoS Med. 2004;1(3):e62.
Tina Sundelin, Mats Lekander, Göran Kecklund, Eus J. W. Van Someren, Andreas Olsson, John Axelsson. Cues of Fatigue: Effects of Sleep Deprivation on Facial Appearance. SLEEP, 2013; DOI: 10.5665/sleep.2964