Being Cold Won’t Give You A Cold, But Losing Sleep Might!

Ever since my med school days I’ve been trying to convince the older women in my family that they will NOT get sick from leaving the house with wet hair. Or walking barefoot, or neglecting to wear a sweater when the outdoor temperature dips below 75 degrees.

I’ve quoted study after study where volunteers (or more likely, paid recruits) were  asked to sit for hours in chilly, damp rooms and were then exposed to droplets containing live cold virus.  Results always confirm that the chilled subjects get sick at the same rate as control groups kept in a more comfortable environment.  Yes, colds are caused by exposure to the hundreds of varieties of upper respiratory viruses out there.  Nothing more, nothing less.

It doesn’t matter. While medical folk are convinced by the data, my mother’s generation just isn’t buying it. It’s too intuitively attractive to believe that viral illness can be kept at bay by staying warm and dry.  So much for that. I’ve let it go and moved on.

But wait just a minute … now researchers have discovered a link between the common cold and lack of sleep, and I think this one may just catch on with a new generation of moms.  A study conducted by Dr. Sheldon Cohen and his colleagues at Carnegie Mellon University in Pittsburgh found that people who lose just a bit of sleep, or those who have poor quality sleep, are more likely to get sick after being exposed to a cold virus than those who get more shut-eye.

They interviewed 153 participants every day for two weeks about their sleep habits. Then the subjects were quarantined and given nose drops containing large doses of cold virus for six consecutive days.  88% of those studied became infected with the virus, but only about half of those actually got sick.  You guessed it — the tired ones were way more likely to get the sniffles.  Volunteers who reported less sleep were more than 5 times as likely to get cold symptoms as those who said they got enough rest.

When you think about it, these results aren’t all that shocking.  But they do confirm what we’ve always known — that we feel better when we get enough sleep, and out of wack when we don’t.  And they suggest that there’s significant interaction between sleep and our immune systems.

We also know that when you’re sick, you need more sleep.  So it makes sense to think that if you don’t sleep that may make you more susceptible, and this study supports that conclusion.  It’s a two-way street.

Intriguing, huh? We don’t yet know how lack of sleep influences immunity, or what other factors may come into play.  In fact, sleep is the big ‘black box’ of medicine in lots of ways. We still have so much to learn about its biological function.

So Grandma had a point, she just got the details wrong.  Instead of  … “Put on a sweater, you’ll catch your death of cold!”, what she meant was …  “It’s bedtime! You’d better go to sleep or you’ll be sick for a week!”