Story highlights Dating websites may warp a person's outlook and expectations, according to a new review

One of the weaknesses of online dating is an over reliance on "profiles"

The abundance of profiles online also may make daters too picky and judgmental

Thanks to the proliferation of online dating, would-be couples are now almost as likely to meet via email or a virtual "wink" as they are through friends and family.

In 1992, when the Internet was still in its infancy, less than 1 percent of Americans met their partners through personal ads or matchmaking services. By 2009, 22 percent of heterosexual couples and 61% of same-sex couples reported meeting online, one survey found.

Single people have more options than ever before, as websites such as Match.com and eHarmony have dramatically widened the pool of potential dating partners. But that may have a downside. According to a new review of online dating written by a team of psychologists from around the country, dating websites may warp a person's outlook and expectations in ways that can actually lower the chances of building a successful relationship.

"Online dating is great. It allows people access to potential partners they otherwise would not have," says Eli J. Finkel, Ph.D., the lead author of the new review, which was commissioned by the Association for Psychological Science and will appear in the February issue of the journal Psychological Science in the Public Interest. "However, specific things the online dating industry does [do] undermine some of its greatness."

One of the weaknesses of online dating is an over reliance on "profiles," the researchers say. Although most dating websites feature photos and detailed, searchable profiles covering everything from personality traits to likes and dislikes, this information isn't necessarily useful in identifying a partner, Finkel and his coauthors write.

That's partly because daters don't always know what they want in a mate -- even though they generally think they do. Studies suggest that people often lack insight into what attracts them to others (and why), and therefore the characteristics they seek out in an online profile may be very different from those that will create a connection in person, the review notes.

"Pretty much all of online dating works through profiles," says Finkel, an associate professor of social psychology at Northwestern University, in Evanston, Illinois. "But you can spend a zillion hours studying profile after profile and, at the end of that Herculean effort, how much closer are you to knowing if there's a romantic spark?"

The abundance of profiles online also may make daters too picky and judgmental, the authors say. The sheer number of options can be overwhelming, and the ease with which people can sift through profiles -- and click on to the next one -- may lead them to "objectify" potential partners and compare them like so many pairs of shoes.

"Online dating creates a shopping mentality, and that is probably not a particularly good way to go about choosing a mate," says Harry Reis, Ph.D., one of the review's authors and a professor of psychology at the University of Rochester Medical Center, in Rochester, New York.

The shopping mindset may be efficient online, but when carried into face-to-face interactions it can make daters overly critical and discourage "fluid, spontaneous interaction" in what is already a charged and potentially awkward situation, Reis and his coauthors write.

Communicating via email or instant message before meeting in person doesn't always cure this problem. Some online communication is a good thing, the researchers say, but too much of it can skew expectations and ultimately sabotage a match. People tend to read too much into emails and other online conversations, which increases the potential for misunderstandings and disappointment, they point out.

Some services, such as eHarmony and PerfectMatch.com, claim to minimize the guesswork involved in online dating by using mathematical algorithms to match couples according to various traits -- including, in one case, the ratio of index- to ring-finger length (said to be a marker of testosterone levels).

The authors of the review are skeptical of these claims. They weren't able to find a single rigorous study showing the effectiveness of the algorithms, and other research suggests it's extremely difficult to predict the likelihood that a relationship will succeed before two people meet.

"Not only is there no scientific evidence, despite the claims, [but] my team of co-authors have become pessimistic that there could ever be in principle an algorithm that could match people well based on the approaches these sites take," Finkel says.

To make matters worse, Finkel and his colleagues say, these algorithm-based services may encourage a counterproductive "destiny" mindset that prizes initial compatibility over other factors that are important to the long-term health of a relationship, such as the social and economic support individuals offer each other, or their ability to cope with stressful life events.

"Certain sites promise much more than they can deliver, and by inducing people to search for that perfect soul mate, they may actually be undermining the very thing [people] most want," Reis says.

None of this, however, means that online dating isn't a good way to meet people. The review stresses that websites are a valuable resource for daters -- as long as a person doesn't put too much stock in the profiles or matchmaking claims.

Finkel, for one, advises online daters to identify promising partners and move the conversation off-line as quickly as possible.

"Don't assume that more time spent browsing profiles is going to improve the odds of meeting someone who is really compatible," he says. "Be as quick and haphazard as you want with that process, because it's not meaningful."

Instead of poring over more profiles and comparing height, weight, occupation, and interests, send a note to a potential date suggesting you meet for coffee or lunch (in a public place), and use that time to get to know the other person, Reis says.

"Don't focus on evaluating that person," he says. "Can you laugh with that person? Can you feel simpatico with that person?"

As Finkel puts it, "There's probably never going to be a substitute for getting two minutes from another person across a cup of coffee."