Couples, please take note. Fighting with your spouse may deteriorate your health, a new study has found.
The findings suggest that married people who fight are more likely to suffer from leaky guts -- a problem that unleashes bacteria into the blood and can drive up disease-causing inflammation.
"We think that this everyday marital distress -- at least for some people -- is causing changes in the gut that lead to inflammation and, potentially, illness," said lead author Janice Kiecolt-Glaser from the Ohio State University.
For the study published in the journal Psychoneuroendocrinology, the team recruited around 50 healthy married couples, surveyed them about their relationships and then encouraged them to discuss and try to resolve a conflict likely to provoke strong disagreement.
The researchers left the couples alone for these discussions, videotaped the 20-minute interactions and later watched how they fought.
They categorised their verbal and non-verbal fighting behaviours, with special interest in hostility -- things such as dramatic eye rolls or criticism of one's partner.
The researchers also compared blood drawn pre-fight to blood drawn post-fight.
Men and women who demonstrated more hostile behaviours during the observed discussions had higher levels of one biomarker for leaky gut -- LPS-binding protein -- than their mellower peers, the researchers said.
Evidence of leaky gut was even greater in study participants who had particularly hostile interactions with their spouses and a history of depression or another mood disorder, they added.
The study found a strong, significant link between hostility and the biomarker LBP, which indicates the presence of bacteria in the blood. And there was a strong link between that biomarker and evidence of inflammation.
Lifestyle changes that could contribute to decreased risk of gut-related inflammation include diets high in lean proteins, healthful fats, fruits, vegetables and whole grains. Probiotics might also be useful, Kiecolt-Glaser noted.