The desired balance in the flow of Chi can be affected by any noxious substance, both external and internal, including poor nutrition, adulterated food, toxic air or water, infectious or contagious diseases, malfunction of an organ, ergonomic or overuse injuries, as well as home, work, sports, and auto injuries. Excessive dampness, wind, cold, heat, even emotional responses to life such as worry, anxiety, stress may affect Chi’s flow through the meridians.