SINCE VIRUSES ENTER YOUR NOSE 24/7, YOUR BODY NEEDS TO MINIMIZE THE NUMBER OF VIRUSES AND BACTERIA THAT ENTER YOUR BODY WHEN YOU SLEEP. THIS LOWERS THE SPEED OF YOUR PULSE AND YOUR BLOOD CELLS ARE LESS ACTIVE AND CAN'T FIGHT SO MANY VIRUSES. WHICH RESULTS IN YOUR RIGHT NOSTRIL TO CONTRACT TO CLOSE ITSELF WHEN YOU SLEEP.