6 Secrets of Kids Who Rarely Get Sick

Regular hand-washing dramatically reduces the passing of respiratory and gastrointestinal illness, so get your kids in the habit of scrubbing up (or using a hand sanitizer) when they leave preschool or day care, after every playdate, and before they eat. Teach kids to sing "Happy Birthday" to themselves twice before rinsing -- scrubbing for 15-20 seconds is key.

Studies indicate that regular, moderate exercise can reduce the number of cold and flu episodes that occur over the course of a year by 25-50 percent, possibly by boosting the circulation of infection-fighting cells. "Exercise is better than any advertised cure or miracle," says Harley A. Rotbart, M.D., Parents advisor and author of Germ Proof Your Kids: the Complete Guide to Protecting (Without Overprotecting) Your Family from Infections.

Make sure kids stick to an early bedtime. Sleep deprivation nearly doubles the risk of getting a cold or flu, Dr. Rotbart says. Most babies need approximately 14 hours of sleep a day; preschoolers need 11-13 hours of Z's.

Cold and flu viruses enter the body through the nose, eyes, and mouth, so help your child keep her hands away from those areas. Yes, it can be very difficult to accomplish -- hand-washing at strategic moments is all the more important. Teach your child never to share a straw, cup, or toothbrush.

Meals with plenty of colorful fruits and vegetables will help boost your child's immune system. Look for foods rich in vitamin C (broccoli, strawberries, and oranges) and vitamin D (tuna, fortified milk, and cereals). Eating yogurt with active cultures (probiotics) can also help build defenses.

The Centers for Disease Control and Prevention (CDC) says it's the single best way to prevent the flu. What are you waiting for?