NEW YORK — Parisa Imanirad, a scientist and cancer researcher from San Francisco, is married and has a wide circle of friends. But once or twice a week, she goes to a restaurant by herself.

Imanirad said dining alone gives her time to think or read. She tries not to touch her phone and relishes the silence.

“It’s like a spa, but a different type,” Imanirad said during a recent solo lunch at Spruce, an upscale restaurant in San Francisco.

Imanirad isn’t alone in her desire to be alone. In the U.S., solo dining reservations have risen 29% over the last two years, according to OpenTable, the restaurant reservation site. They’re up 18% this year in Germany and 14% in the United Kingdom.

Japan even has a special term for solo dining: “ohitorisama,” which means “alone” but with honorifics spoken both before and after the word to make parties of one feel less hesitant. In a recent survey, Japan’s Hot Pepper Gourmet Eating Out Research Institute found that 23% of Japanese people eat out alone, up from 18% in 2018.

As a result, many restaurants in Japan and elsewhere are redoing their seating, changing their menus and adding other special touches to appeal to solo diners.

“Even so-called family restaurants are increasing counter seats for solitary diners, and restaurants are offering courses with smaller servings so a person eating alone gets a variety of dishes,” said Masahiro Inagaki, a senior researcher at the institute.

OpenTable CEO Debby Soo thinks remote work is one reason for the increase, with diners seeking respites from their home offices. But she thinks there are deeper reasons, too.

“I think there’s a broader movement of self-love and self-care and really … enjoying your own company,” Soo said.

The pandemic also made social interactions less feasible and therefore less important while eating out, said Anna Mattila, a professor of lodging management at Penn State University who has studied solo dining. And smartphones help some restaurant patrons feel connected to others even when they’re by themselves, she said.

“The social norms have changed. People don’t look at solo diners anymore and think, ‘You must be a loner,’ ” Mattila said.

The growth comes as more people are living alone. In 2019, Pew Research Center found 38% of U.S. adults ages 25 to 54 were living without a partner, up from 29% in 1990. In Japan, single households make up one-third of the total; that’s expected to climb to 40% by 2040, government data shows.

Increasing interest in solo travel — particularly among travelers ages 55 and over — also leads to more meals alone. On a recent solo trip to Lucerne, Switzerland, Carolyn Ray was stunned when the hostess led her to a beautiful lake-view table set for one, complete with a small vase of flowers. Ray, the CEO and editor of JourneyWoman, a website for solo women travelers over 50, said other restaurants have tried to seat her toward the back or pointedly asked if someone will be joining her.

Ray counsels women planning to dine alone to go somewhere else if they’re treated rudely or given a bad table.

“It’s almost like the world hasn’t caught up with this idea that we are on our own because we want to be on our own, and we’re independent and empowered,” she said. “We can go into any restaurant we want and have a table for one and feel good about it.”

Shawn Singh, a Houston-based content creator and restaurant reviewer, said he eats alone about 70% of the time. If the idea of venturing out for a solitary meal is intimidating, he suggests going to lunch instead of dinner — when tables are usually more crowded with groups — or going early on a weekday.

“The best way to see a restaurant you’ve been wanting to see for a long time is definitely going solo,” Singh said. “If I go at 5 p.m. and alone, I haven’t been denied at one place ever.”