Heart disease is the number one killer of adults over the age of 65 in the United States. Twenty-six hundred Americans die of cardiovascular disease each day, and while smoking and high cholesterol have long been cited as major risk factors, a new book explores how negative emotions can also damage the heart.

Dr. Mimi Guarneri

In The Heart Speaks , Mimi Guarneri, medical director of the Scripps Center for Integrative Medicine in California, documents lessons she's learned from patients. "Whether it's stress or grief or depression, these really affect people," she says. "For example, there's a high incidence of a spouse dying after they hear about the death of their loved one. We now know that 'broken heart syndrome' presents with a very weakened heart muscle, to the point where some people look like they need heart transplants."

Dr. Guarneri advocates treating the physical and the emotional symptoms of illness.

Meditation is one way to help relieve stress on the heart

That could involve teaching patients to meditate, practice Tai Chi, or take a brief time-out when they're under stress. "Just [taking] a deep breath will lower the blood pressure, and start to cause the parasympathetic or calming part of the nervous system to activate."

Dr. Guarneri says that fostering social connections can also help the heart. Her book documents studies showing that people with close-knit community ties have reduced risks of heart disease.