How often do you think about your immune system? Probably not as often as you think about how to avoid the H1N1 swine-flu virus or one of the other viruses afoot these days. If that’s the case, then it’s time to shift your focus. Spending less time thinking about dodging germs and more energy on proactively strengthening your immune system not only helps keep you healthy, it benefits personal wellness on a larger level. “Immunity is not just a defense against sickness; it is synonymous with overall health,” says Kris Somol, ND, an adjunct faculty member at the Bastyr Center for Natural Health in Seattle. “By caring for your immune system, you also heal from injuries faster and prevent chronic disease.” In fact, an underactive immune system is linked to noncontagious diseases, such as cancer. (Cancerous growths can be stunted—or even prevented—by the immune system.)

You might think, given these facts, that you want an immune system that’s ready to mount a defense at the first hint of trouble. And yet, there is such a thing as an overactive immune system. “In some cases, the body fails to recognize harmless invaders, such as pollen, or your own cells as safe and begins attacking them,” Somol explains. This is the case in allergies and autoimmune disorders such as diabetes, lupus, and rheumatoid arthritis. The key to healthy immunity, therefore, is balance. To determine the most effective approaches to boosting immunity, we consulted a spectrum of experts. Here’s what they had to say.