There are several precautions you can take in your day-to-day life to decrease the likelihood of contracting a cold or the flu. Hands should be washed frequently. Whenever possible, use a hand sanitizer with alcohol if you cannot reach a sink. Maintain a germ-free environment for your family and friends. The virus clings to your bare hands, so don't use them to muffle your coughs and sneezes. The next time one starts coming, grab a tissue and throw it away. Cough or sneeze into your elbow if you don't have one. Your eyes, nose, and mouth are the main entry points for cold and flu viruses. You should teach your children not to touch their faces -- and follow your own advice as well. Any activity that gets your heart pumping is aerobic exercise. Your body's natural virus-killing cells are increased by it. Colds are more severe and frequent in heavy smokers. Even being around smoke harms your immune system, your body's defense against germs. Avoid drinking too much alcohol which affects the immune system. And a healthy diet full of vegetables can decrease your likelihood of getting sick.