In a recent piece for The Atlantic, pscyhologist Heidi Grant Halvorson reflected on the idea that at almost 40, she finds more happiness in a quiet Friday night spent curled up reading a book or playing Monopoly with her children than she does going out to do something more "exciting."
"What would my 20-year-old self say if she could see me now?" Halvorson writes. "The answer, of course, is that we all grow up—and for many of us, what it means to be 'happy' slowly evolves into something completely different."
Halvorson's observations line up with a recent study published in Psychology and Aging that suggests that as we age, we spend less time thinking about the things we want to do and more time focusing on the things we already have or do.
Three psychologists wanted to analyze how our perception of happiness change as we age, so they studied 12 million personal blogs using a tool that crawls the Internet searching for mentions of words like "happiness" and "elated."
They found that bloggers in their 20s are more likely to describe themselves as "excited," "elated," or "ecstatic," while bloggers in their 40s and 50s are more likely to use words such as "peaceful," "calm," or "relaxed" when describing their happiness.
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"There are a lot of factors that could contribute to this," says Cassie Mogilner, one of the study's lead authors. "Younger people tend to be geared toward anticipating the future. They're thinking about all the things they want to accomplish or do in the years ahead."
Younger people are also more likely to be exploring new things, meeting new people, or starting new jobs, Mogilner says, whereas older people are a little more set: They tend to see particular people or have more regular routines.
"We found that 20-somethings are five times more likely to use the word 'excited' to describe themselves, whereas those in their 40s and 50s are twice as likely to use the words 'calm' to describe their happiness," she says.
This doesn't mean that everyone automatically "slows down" as they age, just that the things that make them happy tend to change over time.
"That shift from excitement to calm plays a role in people's choices," Mogilner says. "But I'd hope that this could make people be less judgmental. What makes you happy changes. Don't be too hard on yourself when you discover that."