The National Institutes of Health is spending more than a half-million dollars to determine why some couples drink a lot of alcohol and others do not.

The federal agency is looking into "problematic alcohol use in relationships" to try to "improve the health and well being of romantic couples."

The State University of New York at Buffalo is conducting the study, which has received $592,693 in taxpayer funding.

"Understanding the relationship-specific motivations for alcohol use, as well as the risk and protective factors associated with relationship drinking processes as they occur in real-time in couples' natural environments, is crucial to addressing problematic alcohol use in relationships," according to the grant for the project. "This understanding can ultimately inform prevention and intervention efforts to improve the health and well being of romantic couples."

The study aims to inform future research so that theories can be developed about why couples drink.

The research will try to better understand "relationship drinking processes as they occur in real-time in couples' natural environments."

Ultimately, the researchers want to understand why couples differ in how they drink.

"This is a public health concern because some couples continue to drink excessively despite experiencing alcohol-related and relationship problems, whereas others do not," the grant said.

Research for the study included 118 couples writing daily diary reports of "drinking episodes" for almost two months.

The results found that drinking with one's significant other had more positive effects than drinking separately. Researchers also found that "women's relationship drinking is associated with intimacy enhancement, whereas among men it is associated with social effects."