Do you clean your refrigerator regularly, or only after you've run out of space? If your answer is the latter, your refrigerator may be harboring dangerous bacteria that can make you, your family, and your house guests ill.

Refrigerators should be cleaned monthly, inside and out, ideally. The process involves removing all foods, cleaning all shelves, and wiping down drawers. Spoiled food is removed and old containers reclaimed.

The process takes 20 minutes. Here's how to do it.

First, prepare your cleaning stations, including filling a sink with soapy water, and having drying towels handy. Complete this step before you start to remove food from the refrigerator. This limits the amount of time that food has available to reach room temperature.

Next, remove all food from the appliance. Throw out old food past its expiration, and leftovers which have been in containers for more than a few days. Check dairy products for expiration dates -- especially cheeses and creams. Toss fruits and vegetables that have spoiled. Wipe down condiment jars and bottles with a damp towel.

Next, with the refrigerator empty, remove all shelves and drawers and wash them in the water-filled sink. Scrub to remove any caked-on foods and spills. Rinse off the soapy water and dry the part on your drying towels.

Then, while the shelves and drawers are drying, using a mixture of baking soda and water, wipe down the interior surfaces of your appliance. The mixture should be roughly 2 tablespoons of baking soda for every 1 gallon of water. Wipe the mixture off with a clean towel.

Lastly, move the shelves and drawers back into the refrigerator and replace all of the food that's "good".

Refrigerators can be a dirty place. We rarely wash our hands before handling food in a refrigerator and that can contribute to a bacteria-heavy environment. A good cleaning, though, can keep our foods -- and our home -- healthy.

Clean your refrigerator regularly.