But beyond that, forgiving people are markedly physically healthier than unforgiving ones. A 2005 study published in the Journal of Behavioral Medicine found that participants who considered themselves more forgiving had better health across five measures: physical symptoms, the number of medications used, sleep quality, fatigue, and medical complaints. The study authors found that this was because the process of forgiveness tamped down negative emotions and stress.
“The victim relinquishes ideas of revenge, and feels less hostile, angry, or upset about the experience,” the authors wrote.
In 2011, a group of researchers asked 68 married couples to rehash a recent fight, and they recorded the discussion on video. The participants then watched the videos back and described how conciliatorily they behaved toward their partners, using phrases like “I tried to comfort my partner,” or conversely, “I wanted to keep as much distance between us as possible.” The scientists found that the more peaceable the “victims” of each fight were (the ones accused of not doing their fair share of the chores, say, or of invading the other’s privacy), the lower their blood pressure readings were. Their partners’ blood pressure was lower, too. In other words, both granting and receiving forgiveness seemingly brought down the tension level of the entire marriage. Importantly, it didn’t matter whether the instigator of the fight had tried to make amends: “The power to grant forgiveness (and its benefits) rests with victims,” the authors concluded.