Forgiveness may be good for your health, according to the Mayo Clinic. Holding a grudge appears to affect the cardiovascular and nervous systems. In one study, people who focused on a personal grudge had elevated blood pressure and heart rates, as well as increased muscle tension and feelings of being less in control. When asked to imagine forgiving the person who had hurt them, the participants said they felt more positive and relaxed and thus, the changes dissipated. Other studies have shown that forgiveness has positive effects on psychological health, too.