All couples fight, some more often than others, but many of them may be surprised to learn that the more they fight, the longer they live, according to a new U.S. study as quoted by media reports.

　　Couples who suppressed their anger have a mortality rate twice as high as those in which at least one partner stands up for themselves, according to the study, which tracked 192 couples over 17 years.

　　"The key matter is, when the conflict happens, how do you resolve it?" said the lead researcher Ernest Harburg, an emeritus professor with the University of Michigan. "When you don't, if you bury your anger and brood on it and resent the other person or the attacker and you don't try to resolve the problem, then you're in trouble."

　　The findings add to past research showing that the release of anger can be healthy. Individuals who express anger might also have a sense of control and optimism over a situation.

　　Bottled anger adds to stress, which tends to shorten lives, many past studies show.

　　In the current study, the authors suggest a combination of factors to explain the higher mortality for couples who don't express their anger. These include "mutual anger suppression, poor communication [of feelings and issues] and poor problem-solving with medical consequences," they write in the January issue of the Journal of Family Communication.

　　Over a 17-year period, Harburg and his colleagues studied 192 married couples in which spouses ranged in age from 35 to 69, focusing on aggressive behavior considered unfair or undeserved by the person being confronted. Harburg said that if an attack is viewed as fair, the victim doesn't tend to get angry.