If you've been catching colds more frequently, then perhaps it's time to get some long quality sleep.
In a new study conducted by a team of researchers from the University of California San Francisco, University of Pittsburgh Medical Center, and Carnegie Mellon University, short sleep-that is, sleeping for less than 7 hours-can increase the person's risk of catching a common cold by as much as 4 times.
According to the lead author of the study Aric Prather, PhD, who also works as a psychiatry assistant professor of UCSF, short sleep turns out to be one of the biggest determinants of a person's susceptibility to illness. It doesn't matter what the person's lifestyle, habits, and demographics are. If the person lacks sleep, the risk of illness then becomes high.
For the study, Prather worked closely with the team of Carnegie Mellon led by Sheldon Cohen, who becomes the senior author. Both had already worked in a previous study.
To conduct the experiment, the team recruited more than 150 participants from Pittsburgh for a period of 5 years beginning in 2007. Since they were going to be exposed to the common cold virus, the researchers performed a series of health tests and screenings for about 2 months. Before the virus was administered, the natural sleeping habits of these recruits were carefully monitored and analyzed. Each also had a sensor that could keep track of their length of sleep.
After the virus was introduced into the body through a nasal drop, the participants were then placed in a hotel for a week, where the progress of the illness was monitored by collecting mucus samples.
They found that those who slept for 7 hours or more had a reduced risk. Meanwhile, the risk of catching a cold increases the shorter the sleep was.
Although this isn't the first study that aims to establish the relationship between lack of sleep and illness, it is the first to objectively measure it. In this experiment, the team used a person's natural sleeping habit as opposed to forced sleep deprivation.
The study is now published in Sleep.
