This Is the Real Reason You Get So Sleepy When You’re Sick

Updated: Feb. 10, 2017

Have you ever been too tired to even wipe your nose when you're sick? Don't be embarrassed. Science says you have a valid excuse for all that sluggishness.

Why-You-Get-So-Sleepy-When-You're-Sick-According-to-ScienceiStock/KatarzynaBialasiewiczYou don’t need us to tell you that even lifting your head off that soft fluffy pillow when you’re sick can be a challenge. And now thanks to a bunch of worms, you can stay in bed without feeling any guilt at all.

Previous research on microscopic roundworms has shown that when the worms’ cells are under stress, a chemical called, FLP-13, is released. This chemical sends signals to the worms’ brains to fall asleep.

Enterprising scientists at University of Pennsylvania School of Medicine took the research a step further to find out exactly how the chemical works. Researchers noticed a two-part sequence: First, FLP-13 affects the worm’s nervous system by dialing down the activity circuit that helps keep the organism awake, and second, a genetic mutation happens at the same time FLP-13 is present in order for the worm to fall asleep. This mutation causes worms to lack a receptor protein called DSMR-1. Therefore, study co-authors believe DMSR-1 is essential for FLP-13 to trigger sleep. So … what does this all mean to your overall wellness?

“Sleep is vitally important in helping both people and animals to recover during sickness,” says study author David M. Raizen, MD, PhD, an associate professor of neurology and a member of the Center for Sleep and Circadian Neurobiology. “Similar signaling may operate in humans and other animals to regulate sleep during sickness. These findings create a launching pad toward future research into the mechanisms for illness-induced sleepiness in humans and other organisms.”

The next time you catch a cold or are knocked fat with the flu, don’t fight the urge to stay in bed. This isn’t the first time researchers have looked at sleepiness during illness, reports In 2014, a similar study found that fruit flies that slept more when infected with bacteria had greater chances of survival. So next time you’re too sick to head to work head to bed instead, and follow these tips from doctors and nurses to stop a cold in its tracks.