In a 20-year longitudinal study tracking health and marriage quality, BYU family life researcher Rick Miller found that as the quality of marriage holds up over the years, physical health holds up too.

"There's evidence from previous research that marital conflict leads to poor health," Miller said. "But this study also shows happy marriages have a preventative component that keeps you in good health over the years."

A previous BYU study caught national attention when it found that meaningful relationships help individuals live longer. The current study, published in the June issue of the Journal of Marriage and Family, shows positive marriage relationships sustain health over the long run.

The study used data from a nationally representative sample of 1,681 married individuals followed over the course of two decades -- the longest study on marital quality and health to date.

Miller and colleagues measured marital quality in two ways: First, in terms of happiness and satisfaction, and, second, in terms of marital problems (Do you argue about money? Do you fight about in-laws?). Respondents then rated their health on a 1 (excellent) to 4 (poor) scale.

The results showed those with higher marital conflict were more likely to report poor health.

"The implication is that marital conflict is a risk factor for poor health," Miller said. "Couples that fight or argue frequently should get professional help to reduce their conflict because it is affecting their health."

Miller hopes the mounting research on the importance of marriage catches the attention of policy makers. For example, Miller (and many colleagues) believe health insurance should cover marriage counseling because it can help shore up marriage and prevent future health problems.

To that end, sustaining a happy marriage also tends to inspire habits that lead to better health. Happily married spouses encourage one another to stay current on doctor's appointments, sleep better, drink less and participate in healthy activities.

"When spouses have a bad day, in a happy marriage, they're more likely to support each other and empathize with each other," Miller said. "That support reduces stress and helps buffer against a decline in health."

Joseph Olsen, an associate professor in the College of Family, Home and Social Sciences, was a coauthor on the study.