DENVER -- Keeping the bad germs away this season is a big challenge, and the trick may be to incorporate more foods with good germs into your diet.

Nutritionists say buying foods with probiotics can do your body good. A probiotic is a bacteria that is naturally found in your digestive tract. They support the white blood cells and help fight off disease.

"The best thing that we can do for our health is to prevent illnesses, flus, colds, etc., and this is a good way to do that," said Char Leberer, Director of the Nutrition Therapy Institute in Denver.

You can add more of these so-called "good bacteria" by eating certain yogurts, soft cheeses, and even pickles. A new study found probiotics are also effective for kids. Children ages 3 to 5 who took them had fewer cases of colds and flus.

"It's very important for them to have that same good balance of the good bacteria so that their immune system is built up and they won't be so susceptible to the flus and the colds," said Leberer.

The study was published in the journal Pediatrics and said even when kids got sick, if they were eating food containing probiotics, they were sick for fewer days.

When you go to the store, read the label on the product and make sure it says "live active bacteria" or "active culture." That way, you know you're getting the probiotics.

In addition, you should pick up high-fiber foods like green veggies and whole-wheat bread. The live bacteria also need food, and they like to feast on fiber.