Let’s take a closer look at your built-in police force. A group of officers lines up perfectly in your body. Each one has a different job. At the same time, the officers work perfectly as a team. Officer Lymphocyte is a white blood cell. He keeps his eyes open for infection. He scribbles down a description of each invader. That way he can remember it in the future. Next in line comes Officer Lymph Nodes. He produces new cells. These cells fight infections all over the body. Beside him stands Officer Spleen, who cleans out old blood cells from the body.

Like members of any human police force, these guys need the proper equipment to keep doing their jobs. Here are some tips for keeping your immune system police force strong:

Drop and Give Me Twenty! Regular exercise may help flush bacteria out of your lungs. Moving your body around can get your white blood cells moving too. That means they’re just where you want them to be—out on the streets looking for the bad guys!

HONK-shooo, HONK-shoo . . . Studies show that when we get less sleep, our bodies produce fewer lymphocytes. With missing lymphocytes (also called T-cells), you’re more likely to catch a pesky cold or the flu. So bring on the snores!

Scrub-a-dub-dub. Wash your hands with soap and water when you’re dealing with anything extra germy—especially after you use the bathroom. Cover your mouth and nose when you cough or sneeze. In these cases, you have the chance to stop germs from hanging out on your body in the first place. Here, the first line of defense isn’t the immune police force. It’s your own brain!