Smoking, a sedentary lifestyle and unhealthy diet have long been known to increase a person's risks of dying young but a new study suggests that having an unhealthy relationship with partners, family members and friends may also contribute to early death.

Rikke Lund, from the Department of Public Health of the University of Copenhagen in Denmark, and colleagues, conducted a study to examine the link between stressful social relationships and mortality risks. They found that being in constant argument and conflict with family and friends increases a person's risks for premature death.

For the study published in the Journal of Epidemiology & Community Health on May 8, Lund and his colleagues surveyed the social relationships of nearly 10,000 participants of the Danish Longitudinal Study on Work, Unemployment and Health who were between 36 to 52 years old.

During the course of the 11-year study, 422 of the participants died. Cancer was accounted for nearly half of the deaths while the rest were due to heart disease and stroke, liver disease, accidents ad suicide. The researchers then calculated the likelihood of the subjects to die based on how often they argued with their partners, family and friends.

The researchers found that the participants who faced many demands from their partner or children had 50 to 100 percent increased risk of dying. Those with unhealthy relationship with their relatives, friends and neighbors, on the other hand, had up to three times increased death risks. Being jobless also appears to increase the negative effects of a stressful relationship as those who were unemployed were found to be more at risk of dying from any cause than participants who were employed.

Men also appear to be more vulnerable to the effects of arguments and conflicts as those who faced many demands from their family and friends were more than twice as likely to die as women who had the same situation.

"Stressful social relations are associated with increased mortality risk among middle-aged men and women for a variety of different social roles," the researchers wrote. "Those outside the labor force and men seem especially vulnerable to exposure."

Although worries and arguments can be inevitable, Lung said there are risks involved with being often involved in conflicts and intervention may help reduce early deaths linked with unhealthy relationships.

"Intervening in conflicts, particularly for those out of work, may help to curb premature deaths associated with social relationship stressors," she said.