The U-shaped happiness curve dictates that "happiness rises initially to a peak around age 30 and then declines into midlife and then rises again after age 70," according to David Blanchflower, a professor of economics at Dartmouth College.

Blanchflower co-wrote one of the initial research papers that introduced the concept of the U-shaped happiness curve back in 2008. Hundreds of studies since the early 1970s in many countries around the world have shown the same pattern.

But recently, researchers are seeing a major shift as young adults — ages 18 to 25 — report being unhappier now than people in their 40s and 50s.

Research shows that young adults are the unhappiest age group

Blanchflower's most recent working paper, co-authored with Alex Bryson and Xiaowei Xu, shows a change in the pattern, with happiness starting off low in young adulthood and increasing with age.

"We thought it was the U.S., but ... we're seeing it everywhere, and that's why we're panicking," Blanchflower told Scientific American.

Alongside other researchers, Blanchflower analyzed data from the Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System. The paper focused on participants who indicated they experienced, "stress, depression, and problems with emotions," for 30 days in a row in the CDC's survey.

"We have to focus on the people at the extremes," Blanchflower said. "Think about those who are most susceptible to commit suicide, to have deaths of despair. These are the people who say, 'Every day of my life is a bad mental health day.'"

By 2023, researchers saw the greatest increase in responses from people ages 18 to 25, that indicated they experienced the most frequent bad mental health days that year — especially in young women.

"This fact alone is the most striking and scary: my estimates are that 11 percent of ... young women are in despair," Blanchflower told the publication.

Experts agree social media has a negative impact on youth happiness

Blanchflower says he isn't exactly sure why young adults seem to be experiencing the most unhappiness, but notes the downward trend began before the Covid-19 pandemic.

The only potential factor Blanchflower was able to identify is the prevalence of social media and smart phones, citing that the cause of the shift in happiness for young people had to be "something that starts around 2014 or so."

Amber Wimsatt Childs, a clinical psychologist and associate professor in the department of psychiatry at the Yale School of Medicine, has a few theories of her own about why the happiness curve has changed.

"If we do take a zoomed back perspective, we think about war, the associated humanitarian crises, especially the humanitarian crises of late," Wimsatt Childs tells Make It. "But [also] the fact that those crises within the past 20 or 30 years have really just been multiplying."

Wimsatt Child considers how high school and college commencement speeches are leaning more towards themes of the world needing students' creativity and innovation now more than ever to change the state of things.

"And a lot of folks in those seats are thinking like, 'Well, how am I going to afford my higher education? Or how am I going to afford what I've just done? I'm never going to own a home,'" she says.

But Wimsatt Childs agrees with Blanchflower that social media likely plays a role in this new pattern of unhappiness. "What social media has done in a lot of ways is it has amplified concerns that were already well underway," she says. "What social media did was put it on a big screen for people."

Social media — apps like Snapchat, Instagram and TikTok — floods people with information and can lead to comparison among peers on a larger scale, she adds.

People have always compared themselves to others, but "that might have been restricted in range to people that are much more proximal to us, like a subset of folks in your neighborhood in your community," Wimsatt Childs says.

How young adults can start to experience more happiness now

Wimsatt Childs has some advice for young adults on how they can experience more happiness in their younger years.

1. Decide what your values are and structure your behaviors to align with them: "We tend to live our best lives, when we engage in behaviors that are aligned with the things that are part of our deeply held beliefs," she says.
2. Become more aware of unhelpful comparisons and use comparison for your benefit: Comparison doesn't always have to be a negative thing, Wimsatt Childs notes. If you use comparison to be more grateful for what you have such as having food to eat or a roof over your head, then it can be a helpful tool.
3. Focus on reducing stress levels: Too much stress can lead to health issues including heart problems, she says. "Doing what they can to navigate exposure to all these sources of stress can be helpful," including avoiding social media use right before bed, prioritizing sleep hygiene and exercise.

She also encourages parents and loved ones of young adults to educate themselves on the different challenges and stressors that those in their late teens and early 20s are faced with.

Wimsatt Childs then suggests validating young adults whenever they express that they're struggling with their mental health and making yourself available to engage in healthy activities with them like having open discussions about emotions or taking walks together.

Most importantly, she says, "when people are seeing their young people struggle, making recommendations to them, and validating that it is okay, it's expected [and] it's a good thing for them to seek out professional support," like a therapist whenever they're in need.

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