ItÕs winter.  MankindÕs common enemy, the common cold, is wreaking havoic everywhere.

         People try almost anything to stop colds. There are thousands of remedies, varying from echinacea and zinc to commercial formulations created by schoolteachers and herbalists.  Though only a very few have been shown to work better than placebo, they still bring in billions of dollars every year.  Placebos are both useful and extraordinarily profitable.

         Yet what if I told you there are simple measures you can do that even during  Òcold seasonÓ decrease your chances of feeling miserable for days and weeks.  Would you try them? Would you take the time to do something more than down a pill?

         Before you answer, let me tell you about a recent study at Carnegie-Mellon.  One hundred fifty three people, all healthy, aged 21-55, volunteered to try and catch a cold.   Their job was to register what they did over two weeks, then have cold viruses infused in their noses.

         What differentiated those who got sick from those who didnÕt?  Not socioeconomic group, or job, or medical condition.  What made the difference was how long and how well people slept.

         The group that slept less than 7 hours had three times the number of colds than those who slept 8 hours or more.  More surprising, those with a sleep efficiency of 92% or less  had nearly six times as many colds as those with a sleep efficiency of 98%.

         What is sleep efficiency?  Time asleep divided by time in bed.  If you go into bed 8 hours, and sleep 7, your sleep efficiency is 87.5%, enough to set you up for higher risks of catching colds.

         The study will need replication, but it points out something thatÕs been known for nearly 40 years Ð rest a subject before putting viruses into their environment and the infection rate goes way down.

         Rest works.  Your body is rebuilt all the time, and needs the process of rest to stay healthy.

         Besides sleeping and assuring adequate rest, there are other ways to combat colds.  Here are a few easy ones:

         1. Keep your hands from your face.  If you want to know how often you touch your face, just put a little colored ink on your fingers.  Stay away from the mirror for a few hours, then take a look.
         Most of the population unconsciously frequently  touches hand to face.  ItÕs hard to control roving hands when asleep or when waking up, but itÕs easier when youÕre fully awake.
         If you must touch hands to head, touch the back and sides.  Stay away from three major areas Ð mouth, nose, and eyes.  These are portals for bugs, though of the three your mouth has perhaps more ways of discouraging intruders.

         2. Wash your hands.  Few people wash their hands before and after meals, and fewer still during the normal day.  Since bugs go quickly from your hands to places that cause infection, thatÕs a mistake.
         These days many people use different alcohol preparations to clean themselves.  If youÕre not near a sink, they are a useful alternative.
         But donÕt believe all that advertising hype about Òkilling all germsÓ or Òdestroying 99.5% of infectious agents.Ó Those viruses and many bacteria exist in the air.  Clear your arm of bugs, and within a few hours it will be colonized by dozens of other bugs.
         Physically contacting others, particularly shaking hands, is a great way to spread germs.  When in doubt, wash your hands.

         3. Think like a bug.
         Bugs just want to survive. If they can, they also want to reproduce.          Yet their environment is harsh.  Consider that there are 100 trillion critters living in or around your body.  Those critters want to keep other critters out.
         Ever consider where antibiotics originally came from?  Plants and animals, thatÕs who:  They developed their own means of fighting and killing viruses, bacteria, and fungi. 
         If youÕre a virus moving through the air, you want to find a pleasant organism that will allow you to live there a while.  ThatÕs hard to do in the desert.

         But in an airplane, or on a crowded bus, or in a schoolroom, youÕve got a chance.  There are plenty of potential ÒhostsÓ hanging around, touching each other and the furniture and coughing on each other.  Especially in packed airplanes, which recycle stale dry air at the  atmosphere of  6000 feet, a virus has got a chance.  No wonder a fifth of people get sick after plane flights.

         Yet when you finally reach your victimÕs nose, or eyes, or mouth, you face a daunting fact Ð others got there first.  Billions of them.  A few are like you, but most want you to clear off Ð or theyÕll kill you.

         ThatÕs where immunity comes in. Your immune system, when alert, can take on pretty much anything.

         Which why you need rest.  Resting well keeps your immune system up, plus a lot else. Proper rest can make your life more fun, and a lot more cold-free.

Dr. Matthew Edlund practices sleep medicine and psychiatry in Sarasota.  His new book, Designed To Last, is available online. He can be reached at 365-4308 and via his Web site at doctoredlund.com.