Researchers, led by UC San Francisco, tested the effectiveness of a weeklong web-based wellbeing intervention, known as the Big Joy Project. This consisted of daily micro-acts, which included asking someone to share a fun, inspiring, or proud moment, making a gratitude list, and performing a kind act to brighten someone's day. Approximately 17,600 people from around the world participated: most were from the U.S., Canada, and Great Britain (71%), female (84%), white (74%), with at least some college education (94%).
What They Discovered
After the seven-day intervention, participants reported higher levels of wellbeing and positive emotions, and a stronger belief that one's own behavior can promote happiness. They also reported decreased stress, and improved health and sleep quality.
Younger, Black and Hispanic, and socially disadvantaged participants benefited the most.
Why It Matters
Improvements in wellbeing are associated with a lower risk of future mental illness and better physical health. "People with higher wellbeing are less likely to develop chronic conditions, like cardiovascular diseases, and have reduced mortality in both healthy and unhealthy populations," said senior author Elissa Epel , PhD.
Web-based wellbeing interventions that last several weeks and take three to four hours a week to complete have shown favorable results. But this is the first time that a short intervention has shown such strong benefits, and it could work for more people.
"Many people lack the time, motivation, and resources to commit to these lengthier programs, and they may be more likely to drop out," said first author Darwin Guevarra, PhD, who is also affiliated with Miami University. "We were excited to get positive results in a program that required just a few minutes each day for a week."
Publication: Journal of Medical Internet Research (June 4, 2025)
Other authors: Yoobin Park , PhD, and Jin Liou of UCSF; Xuhai Xu, PhD, of Columbia University; Jolene Smith and Peggy Callahan of Mission: JOY; Emiliana Simon-Thomas, PhD, of UC Berkeley.
Funding and disclosures: Smith and Callahan are from the nonprofit that partially funded the Big Joy Project.
