Our body is one unit made of many sub-units that are all connected.   A problem in one unit can and  will affect other units.  This includes the mind and body as well  (mental and physical health)

The body's condition affects the mind, the mind's condition affects the body.  From a whollistic point of view, if a cause of a particular problem is not found, and not eliminated from the body, the body will degenerate  until negative effects accumulate on deeper levels,  eventually causing a constitutional weakness that results  in severe  health problems.  These becomes the chronic  degenerative diseases.