Why Are All-Nighters Terrible For You?

Pulling an all-nighter, whether it’s for studies, work, or fun, is something we’ve all done. All-nighters refer to a night of total sleep deprivation and is, unfortunately, a common reality of our world, especially among professionals or students. In a St Lawrence University study, around 60% of student participants reported staying awake through the night at least once since they started school.1

All-nighters may not be completely avoidable, but researchers are emphatic about its negative consequences on the circadian rhythm, metabolism, and cognitive function. Here are a few things that can go wrong when your night sleep is compromised and you are sleep-deprived.


Increases Stress Hormones

A study published in the Journal of Cognitive Neurology by Yeon Joo et al. reported that sleep loss increases the production of the stress hormone cortisol.2 This in turn can weaken the immune system and make the body susceptible to a host of infections.

Heightens Blood Pressure

People who frequently pull all-nighters may be at a greater risk for chronic conditions such as high blood pressure, high cholesterol, and even Type 2 diabetes. Loss of sleep also plays a role in thyroid hormone production.


Reduces Immunity

Sleep deprivation has been found to reduce the body’s cellular immune function.3 Every time you sleep, your brain recharges itself and when you are sleep-deprived you are denying it a chance for this all-important reboot. The brain also detoxes during the sleep phase and when there has been prolonged lack of sleep, metabolites that normally get flushed out build up in the brain.

Disturbs Circadian Body Clock

Staying up all day and night can wreak havoc on the circadian body clock and its signaling, throwing it out of balance. A wrecked circadian rhythm can make you feel nauseous, tired, and even dizzy.


Impairs Cognitive Function

Loss of sleep interferes with the brain’s cognitive ability. So, basically, your thinking power diminishes when you give up on sleep. When you stay awake for long hours at a stretch, your brain uses up more of fuel molecules called adenosine triphosphate (ATP). As the brain burns more ATP, you become less cognitively efficient and your judgment becomes impaired. This can also have serious implications for your safety. According to a University of Berkeley study, sleep deprivation hampers our ability to read facial expressions accurately. Sleep-deprived participants in the study were unable to accurately distinguish between friendly and threatening faces. There was also a disconnect in the brain-heart neural link which usually helps the body recognize distress signals. “Consider the implications for students pulling all-nighters, emergency-room medical staff, military fighters in war zones and police officers on graveyard shifts,” lead author Goldstein-Piekarski said4

Affects Your Emotional Quotient

Loss of sleep can also wreak havoc on your emotional quotient and reduce your quality of life. Negative thinking, moodiness, irritability, and anger are corollaries of lack of sleep. According to researchers Vandekerckhove and Cluydts, “deprivation of sleep makes us more sensitive to emotional and stressful stimuli and events in particular.”5 Prolonged lack of night sleep has been linked to depression and even post-traumatic stress disorder. A Behavioral Sleep Medicine journal study on 120 university students by P. V. Thacher showed that all-nighters were associated with poorer academic achievement and a trend for depression.6


Pulling an all-nighter once in a way may be fine, but you can’t afford to make it a chronic habit. Remember, sleep is an absolute requisite to keep you healthy, and your body and mind will definitely act up if you push them to the edge.