Sticks and stones may hurt you, and so can words — if you’re always using them to fight with a loved one. According to a new Danish study published in the Journal of Epidemiology & Community Health, stressful relationships can lead to an earlier death.

The researchers used data from the Danish Longitudinal Study on Work, Unemployment and Health, which included 9,875 men and women aged 36 to 52 years. The study tracked their health from 2000 to 2011; they found that men and people without jobs were the most susceptible.

“Stressful social relations are associated with increased mortality risk among middle-aged men and women for a variety of different social roles,” Rikke Lund, a public health researcher at the University of Copenhagen, and her colleagues found. “Those outside the labour force and men seem especially vulnerable to exposure.”

They measured stressful social relations, partners, children, relatives, friends, and neighbors and examined the answers to questions regarding these relationships. “Less is known about the health consequences of stressful aspects of social relations, such as conflicts, worries and demands,” the authors wrote.

“Conflicts, especially, were associated with higher mortality risk regardless of whom was the source of the conflict,” they continued. “Worries and demands were only associated with mortality risk if they were related to partner or children.” Ten percent of participants said that their partner or child was always the source of their worries; six percent said they always or often had conflicts with other family members; and two percent had conflicts with friends often or always.

The authors concluded that the participants who always felt stress or demands from their children had a 50 percent increase of death risk. “I think it really adds to our broader understanding of the influence of relationships, not only on our overall health, but on our longevity — how long we actually live,” Julianne Holt-Lunstad told Reuters Health. (She was not involved in the study).

She went on to further explain to Reuters that relationships, like food and exercise, play a vital role in the relationships we have. “But not all relationships are equal — we need to be careful about the negative aspects as well,” she said.

The opposite of this is true: A 2013 study found that being in love and having a fulfilling love life can help you to live longer. "Research shows that people in loving relationships have a lower death rate than single people, even people who have unhealthy lifestyles tend to live longer than those who lack social and community support," according to Sunil Mittal, psychiatrist and director of Cosmos Institute of Mental Health and Behavioral Sciences, Med India reported. “The study attributes a person's longer lifespan to high self-esteem due to his or her partner's positive feedback, which lowers the chances of depression.”

However, Holt-Lunstad thinks that people shouldn’t go to the extreme and end all imperfect relationships either.

“We know that social isolation is bad for us as well,” she said. “They’re probably both bad and that’s why it might be important to foster the positive aspects rather than just focusing on cutting people out of your life.”

Source: Lund R, Christensen U, Nilsson CJ, Kriegbaum M, Rod NH. J Epidemiol Community Health. 2014.