Catch some sleep to avoid catching a cold

BY ELLI TIAN

As college students, we know all too well the value of a good night’s sleep. Getting enough sleep can improve one’s mood, help with long-term memory formation and lower one’s risk of developing chronic diseases.

According to a new study by researchers at the University of California, San Francisco (UCSF), sleeping for at least seven hours a night on a regular basis can also dramatically lower one’s risk for acquiring more common illnesses such as the common cold.

Previous research has long suggested a link between sleep and susceptibility to illness. In particular, lack of sleep affects the production of T cells, a type of white blood cell that allows the immune system to respond to foreign antigens. A decrease in a body’s T cell production not only increases one’s chance of getting sick, but also decreases the body’s ability to fight off these antigens, resulting in longer and more frequent periods of illness.

Many past studies have relied on participants’ self-reports of variables such as their daily habits and their quality of sleep. This reliance on self-reporting can result in bias, which puts the validity of these studies’ conclusions in question.

The researchers at UCSF were the first to attempt to measure these variables objectively, using standardized health screenings, watch-like sleep sensors and nasal drops containing regulated amounts of the cold virus.

Participants were first monitored for two months in order to establish baselines for their health status. Their sleep patterns were then recorded for a week and then the participants were given doses of the cold virus and monitored for an additional week to determine whether or not the virus took effect. The severity of the participants’ cold symptoms was measured through laboratory analysis of nasal secretions and measurements of mucus production.

Analysis of the data revealed that, after controlling for demographic differences, participants who slept less than seven hours a night were 4.2 times more likely to catch a cold than were participants who slept more than seven hours, and this difference was statistically significant. There was a strong linear association between the variables, with longer hours of sleep correlating with a decreased risk of illness. In comparison, the risk posed by other factors, such as family history and stress levels, was found to be negligible.

Even though the study doesn’t explore the mechanisms of how sleep affects susceptibility to the common cold, it still has huge implications for medicine and public health. A survey by the National Sleep Foundation estimates that as many as one in five Americans gets an average of less than six hours of sleep. The Centers for Disease Control and Prevention (CDC) has also declared lack of sleep a public health epidemic, estimating that 50 to 70 million American adults are affected by a medical sleep disorder and that almost twice as many may have difficulty sleeping. The effects of sleep insufficiency can be quite widespread — people who don’t sleep enough are more likely to get into car accidents and perform poorly at their jobs.

Getting enough sleep may not seem that crucial when there’s a lot of work to be done, but the CDC continues to stress the importance of good sleep habits for an individual’s well-being. So before you pull that next all-nighter, try to think about whether your body would be grateful to receive a good night’s sleep instead.