This article originally appeared on Fatherly.
Men, if your marriage is getting better over time odds are that your cardiovascular health is improving too, according to a new study based on 19 years of data. Conversely, the research suggests, as marital quality declines husbands are at increased risk for cardiovascular disease. Marriages that are consistently good—or consistently bad—did not come with such health consequences, which could explain why some of the unhappiest husbands seem to to live forever.
“An apparent link between marriage and health is a consistent finding across many studies, going back as far as 1912,” study coauthor Ian Bennett-Britton of the University of Bristol told Health Day. “What’s not been clear is whether this is simply a reflection of healthier and wealthier people getting married or a true protective effect of the marriage itself.”
Indeed, scientists have been trying to link marital status to health for more than 100 years. But more recent research suggests that many of these early findings may have been skewed by economics, and that marital status may not matter as much as employment status (and by extension, socioeconomic status). Since people who are unemployed throughout their lifetimes are less likely to get married, the theory goes, mortality, unemployment, and bachelorhood go together.
But until now, few researchers had examined how marriage specifically affects cardiovascular health. To fill this void, Bennett-Britton and his colleagues looked at relationship and health data from 620 married fathers. When their kids were 3-years-old, the dads completed a 12-item survey to gauge the state of their marriages, and then they took the survey again when their children were 9-years-old. Relationship quality fell into one of four buckets: consistently good, consistently bad, improving, or deteriorating. They were then evaluated again when their kids were 19-years-old.
Even after controlling for variables such as age and household income, the researchers found that men in improving relationships had lower levels of “bad” LDL cholesterol and lower BMIs compared to dads in consistently good, consistently bad, or deteriorating relationships. Men in deteriorating relationships also had higher diastolic blood pressure, long term.
Why men in consistently bad relationships are better of than men in deteriorating ones remains something of a mystery. One possibility is that the quality of a marriage just doesn’t matter that much when it comes to heart health. Another possibility is that our hearts take a beating when our situation is in flux—but men in stable, bad relationships are fine (at least, cardiovascularly speaking) “The similarity of CVD risk factors for men in persistently good and bad marriages suggests a number of possibilities,” study authors write. “That quality of marital relationship is unimportant; that there could be some habituation after a period of time.”
While the results are promising for young parents working to improve their relationship for the long haul, they should be taken with a grain of salt (if you have heart problems, don’t take grains of salt). The sample was relatively small, did not include any data on women, and researchers did not take into account cigarette or alcohol use, which is linked with both marital stress and poor heart health.
“The long-term impact of these changes is difficult to ascertain,” Rahul Potluri, a cardiologist and marriage researcher of Aston University (who was not involved in the study), told Health Day. Potluri adds that, while it is possible that deteriorating marriages lead to poor health, it is also possible that the converse is true—poor health can certainly puts a strain on a marriage.