A new study finds it could ease anxiety and depression and reverse years of attention decline, with lasting results

Blocking the internet on your smartphone for just two weeks can lead to better mood and mental health—and may significantly improve your attention span, even making you feel as if you’re 10 years younger, new research suggests. Those effects continue even after internet access is restored.

The study, published earlier this year [February 2025] in PNAS Nexus, is the first to measure how cutting off mobile phone internet use affects the brain and mood. While the methods differ from clinical psychology studies, a group of U.S. and Canadian researchers from diverse fields says its results are remarkable.

“These results provide causal evidence that blocking mobile internet can improve important psychological outcomes, and suggest that maintaining the status quo of constant connection to the internet may be detrimental to time use, cognitive functioning, and well-being,” the researchers say.

“Despite the many benefits mobile internet offers, reducing the constant connection to the digital world can have large positive effects,” they add.

Key findings of the study include:

• Better mental health: The reduction in depressive symptoms was larger than what’s typically seen with antidepressants and similar to the effects of cognitive behavioral therapy. The researchers asked about symptoms such as “feeling down, depressed, or hopeless,” and “having little pleasure or interest in doing things.”
• Improved attention: Blocking mobile internet use reversed the equivalent of 10 years of typical age-related attention decline, the researchers say. They measured this by giving people a widely-used task in which they had to pay attention to changing images on a screen and react to only certain kinds of images and not others. Sustained attention typically starts to decline a little bit each year after age 40, the researchers say. That means our attention on challenging tasks at age 50 is, on average, worse than it was at age 40.
• Lasting effects: Mental health and well-being continued to improve even after internet access was restored.

“These results show that using smartphones less can improve how we feel and how easily we can focus our attention,” says lead author Dr. Noah Castelo of the University of Alberta in Canada. “Setting time limits on how long you can use certain apps might help people who feel like their attention is increasingly fragmented.”

Unplugging from smartphone internet brings benefits  

The research comes at a time when nearly 90% of American adults own a smartphone, with the average user spending about 4.6 hours daily on their devices, one survey shows. 

While other devices like laptops and tablets can also distract, smartphones are especially disruptive due to their constant presence, the researchers say. About 95% of people used their phones during their last social event, far more than with any other digital device.

At the same time, half of U.S. smartphone users—and the majority of those under age 30—worry that they use their device too much, as evidence grows linking smartphone use to declines in mental health and brain function, including behavioral and cognitive self-control.

Another report published this month [April 2025] indicates that excessive screen time among adolescents negatively impacts multiple aspects of sleep, which in turn increases the risk of depressive symptoms, particularly among girls.

In this study, most—but not all—of the participants felt better after the mobile internet block. About 70% reported improved mental health, 73% experienced greater well-being, and roughly 59% showed better focus and attention.

Participants said they spent more time offline, pursued hobbies, went outside, and socialized in person. They also consumed less media, exercised more, and slept about 18 minutes more each night. Time spent texting or talking online remained unchanged.

Individuals also reported feeling more socially connected, which helped reduce symptoms of anxiety and depression. When researchers analyzed the overall effects, they found clear boosts in mood and mental health and smaller but measurable gains in attention.

“These improvements can be partially explained by the intervention’s impact on how people spent their time; when people did not have access to mobile internet, they spent more time socializing in person, exercising, and being in nature,” the researchers say.

Screen time plummets with blocked mobile internet

The randomized trial included 467 adults with an average age of 32, about 60% of whom identify as female and White. Of the group, 29% were students, 42% worked full-time, and 16% worked part-time.

Before the study, participants uploaded screenshots of their iPhones’ screen time data to track mobile use. A mobile app called Freedom was then used to block all mobile internet access (while still allowing calls, texts, and desktop internet).

The individuals were divided into two groups. The first group blocked mobile internet for the first two weeks, while the second acted as a control group for the first two weeks before blocking it. 

Of the 119 people (25.5%) who maintained the block for at least 10 of the 14 days:

• Group 1’s average screen time fell from 314 minutes to 161 minutes, then rose to 265 minutes afterward.
• Group 2 saw similar benefits when they also began the block, with average screen time dropping sharply to 190 minutes from 336.
• People who blocked mobile internet for at least 10 days showed stronger improvements than others in mental health, well-being, and—to a lesser extent—attention. 

Participants who followed the block for at least 10 days had better mental health and attention than others before the study began, which may limit how widely the findings apply, the researchers note. Participants also knew the study was about smartphone use, possibly affecting their behavior.

Blocking mobile internet at specific times of day or on certain days might make it potentially more effective, the researchers say. Balancing the practical benefits that smartphones offer against these significant negative consequences is an important task for users, they say.

“Our results suggest that, for many people, spending less time with their device can help achieve this balance.”

Reference

Castelo N, Kushlev K, Ward AF, Esterman M, Reiner PB. Blocking mobile internet on smartphones improves sustained attention, mental health, and subjective well-being. PNAS Nexus. 2025;4(2). doi:10.1093/pnasnexus/pgaf017