German researchers find singles who spend their free time helping friends or neighbors are more likely to be in a relationship one year later.

Volunteers help assemble meals at a Target Party for Good in New York City. (Photo: lev radin/Shutterstock)

There is no shortage of alleged wisdom regarding how to find a mate. But the results of a new German study point to a surprising way to boost your prospects.

Volunteer at a food bank. Take part in a neighborhood clean-up campaign. Or at least check to see if an elderly neighbor could use some assistance.

University of Cologne psychologists Olga Stavrova and Daniel Ehlebracht report altruistic behavior "is not only desirable in hypothetical partners, but also helps individuals acquire a romantic partner in real life."

Specifically, they write in the journal Social Psychological and Personality Science, "Among single individuals, engaging in pro-social behavior in any given year was associated with increased odds of finding a partner and entering into a romantic relationship in the following year."

Altruistic behavior "is not only desirable in hypothetical partners, but also helps individuals acquire a romantic partner in real life."

Who knew picking up cigarette butts was sexy?

The researchers used data from the German Socio-Economic Panel, an annual survey that has been conducted by the German Institute of Economic Research since 1984. Ten times over the years, participants "were asked to indicate how often they engaged in a number of activities in their free time, including 'helping out friends, relatives or neighbors.'"

They answered on a scale of one (at least weekly) to four (never). To measure their general level of social activity, they also revealed how much time they spent "spending time with friends, relatives or neighbors."

Stavrova and Ehlebracht focused on the 12,775 participants who reported being single on one or more of the years when those questions were asked, and checked if their relationship status had shifted the next year. Approximately 14 percent changed their status to either married or "have a steady partner," but that overall figure masked an important distinction.

"In any given time period," the researchers write, "individuals reporting a high frequency of pro-social behavior were more likely to indicate a relationship status change from single to partnered than their less pro-social counterparts. For every one-point increase in the frequency of helping behavior, the likelihood of being in an intimate relationship in the subsequent year was between 25 percent and 46 percent higher."

This effect persisted even after accounting for overall levels of social involvement. What's more, reverse causality seems unlikely, since "individuals who started a romantic relationship did not experience an increase in helping behavior compared with those who remained single."

Stavrova and Ehlebracht argue their results are best explained by evolutionary psychology. Much as driving an expensive car indicates wealth, they write, altruistic behavior "may represent a 'courtship display' that signals the presence of good character, or good parenting qualities."

So if you are frustrated about being single, find a non-profit you believe in and start volunteering. You'll be doing some good for your community—and increasing the increasing the odds of attracting that special someone.