This article originally appeared in MindBodyGreen.

In this new age of coronavirus, immunity is certainly top of mind. As it should be—after all, a healthy body is dependent on a strong immune system, which helps us fend off not only viruses like COVID-19 but also pathogenic bacteria and parasites.

While supporting the immune system is important, it raises the question: How do we know if our immune system is lagging in the first place?

Chronic diseases or autoimmune diseases are the most obvious risk factors for impaired immunity. But "there are definitely things lifestyle-wise that can set you up for infection," says Randy Horwitz, M.D., Ph.D., immunologist and medical director of the Arizona Center for Integrative Medicine. For the generally healthy population with no underlying medical conditions, these can include an unhealthy diet, a high-stress job or home environment, and poor sleep.