Dr. S. I. McMillan in his book, None of These Diseases
"the verbal expression of animosity toward others calls forth certain hormones from the pituatary, adrenal, thyroid, and other glands an excess of which can cause disease in any part of the body. Examples are: ulcers, high blood pressure, hardening of the arteries, heart disease, kidney disease, diabetes, Colitis, strokes, headache, arthritis, many mental disturbances.