If you're lonely but introverted, the thought of doing something like joining a book club, attending church or signing up for online dating might seem daunting.

It might be a relief — or validation, even — to know there is research that says low-stakes activities can make you feel happier, increasing feelings of belonging and connection.

All you have to do is make small talk with a stranger.

According to research conducted by the University of Chicago and a joint study by the University of Sussex and the University of British Columbia, people reported an increase in happiness when they were asked to engage in easy interactions, like chit chatting with fellow commuters, having a brief conversation with a coffee shop barista or just making eye contact with other people. Even something as simple as saying "Hello" or thanking someone "predicted greater life satisfaction," according to a recent study.

Researchers say that greeting the mail carrier or saying thanks to a bus driver may be an easy way to boost subjective well-being.

And that can help with loneliness, according to Joe Keohane. The New York-based journalist and author recently wrote a book about what we gain from talking with people we don't know. It's called "The Power of Strangers: The Benefit of Connecting in a Suspicious World."

"You don't need to have a deep personal conversation with someone in order to experience the benefits," said Keohane. "A passing interaction with a barista, a five-second conversation about the weather or asking someone how they're doing and actually listening to what they say and wishing them well, those sort of minimal social interactions can actually be a pretty powerful way to treat feelings of loneliness and isolation."

If it's so easy, why don't we do it more often?

We may be remembering the advice we got as children: Don't talk to strangers. As adults, however, we might not be worried about putting ourselves in danger, but violating a social norm if we strike up a conversation on the train or in the grocery checkout line. We're afraid that initiating a conversation with someone we don't know will be perceived as uncomfortable, awkward and unwelcome.

People worry that they're "just going to be bad at it, that they'll make a fool of themselves, that they'll feel terrible afterwards," Keohane said.

But we're being too pessimistic about what will happen if we talk to a stranger.

According to a study by researchers at Cornell, Yale and Harvard, people underestimate how much others like them after a first meeting. People in that study said that striking up a conversation was easier than they thought it would be, and in yet another study, people said that initiating conversations ended up being more rewarding than they expected.

Keohane considers these brief encounters "healthy snacks" in a varied diet of interpersonal relationships, supplements to main meals of deep friendships, true love and family ties.

"Is talking to strangers going to reduce the loneliness that comes with, say, having just lost your spouse? No. But it might reduce feelings of loneliness for a while by increasing feelings of connection and belonging, albeit on a small scale," according to Gillian Sandstrom, a psychologist from the University of Sussex who has extensively studied social interactions with strangers and casual acquaintances.

Conversations with strangers "might remind you that there are people out there that you can connect with. It might get you out of your own head for a bit. It might help you practice your social skills and build your confidence," she said.

And it might lead to a deeper connection.

In one study conducted by Sandstrom and her colleagues, people were asked to participate in a week-long scavenger hunt of sorts; find someone drinking coffee, someone wearing an interesting T-shirt or someone carrying an awkward object and then talk with them. At the end of the week, 41% of the participants said they exchanged contact information with at least one of their conversation partners.

Keohane cautioned that you want to be in a safe environment when connecting with strangers.

To make connections with others, he suggests getting in the habit of making eye contact when you say hello to the cashier, bus driver or waiter. He recommends a slightly unusual greeting to unlock conversations that may go a bit deeper than our rote scripts of, "How are you doing?" "Fine," or "Have a nice day," "You, too."

Keohane likes to greet store clerks with the question, "Are people behaving themselves today?" He said that empathetic phrase often leads to interesting responses. Or, if someone asks him how he's doing, Keohane might say, "I'm a 7 out of 10. How about you?" That often sparks a conversation, he said.

Keohane also likes to break the ice by acknowledging to strangers that what he's doing might be a bit outside of the social norm. For example, he might say: "I know people don't talk on the train, but I really like your shoes."

"What that does is lower people's defenses a little bit," Keohane said.