Unfortunately, most of us know what it feels like to have a cold or catch the flu. Even more unfortunately, a lot of people don't really know the proper steps to avoid catching anything that's going around. Sure, washing your hands and dodging airborne coughs and sneezes from coworkers doesn't hurt, but the best way to keep your health in tip-top shape is to build up your immune system from the inside out.

Exercise

When you work out, you energize the cells in your body that are responsible for fighting off illness-causing bacteria.  “Walking, bouncing, and even vibration modalities have all been shown to increase immune function and lymphatic drainage,” says fitness trainer and health coach, Clint Fuqua. “Meanwhile, short intense bouts of exercise have been shown to kill off viruses before they can infect your system.” Be careful not to overdo it, though. Exercising too much without giving your body the rest it needs can actually backfire and hurt your immune system.

Diet

Not surprisingly, making sure that you are sufficiently hydrated and getting the proper nutrition from the foods you eat is a key component to keeping your immune system strong. Fuqua recommends eliminating sugar and increasing your intake of fruits and vegetables to increase your body’s production of antibodies. “Quality proteins and essential fats,” he adds, “further aid in the production of immune cells and hormones needed for overall health and immune function.”

Sleep

Making sure that you get enough sleep every night is another crucial part of keeping your immune system strong. “Our bodies produce increased amounts of proteins called cytokines during sleep,” says Dr. Robert Rosenberg, board-certified sleep medicine physician and author of Sleep Soundly Every Night, Feel Fantastic Every Day. “These are necessary for fighting infection and regulating sleep itself. When we are sleep-deprived, the production of some of these cytokines becomes abnormal and can promote inflammation and hinder our ability to fight infections.”

Destress