Possessing a smartphone before the age of 13 correlates with diminished mental health and well-being in early adulthood, as indicated by a global study including over 100,000 adolescents.

A study published today in the peer-reviewed Journal of Human Development and Capabilities revealed that individuals aged 18 to 24 who acquired their first smartphone at age 12 or younger were more prone to report suicidal ideation, aggression, dissociation, inadequate emotional regulation, and diminished self-esteem.

The research indicates that the effects of early smartphone ownership are largely linked to early social media access and increased risks of cyberbullying, interrupted sleep, and deteriorating family connections in adulthood.

A consortium of specialists from Sapien Labs, which maintains the largest global database on mental wellbeing, the Global Mind Project—source of the data for this research—are advocating for immediate measures to safeguard the mental health of future generations.

“Our data indicate that early smartphone ownership—and the social media access it often brings—is linked with a profound shift in mind health and wellbeing in early adulthood,” states primary author Dr. Tara Thiagarajan, a neuroscientist and the founder and Chief Scientist of Sapien Labs.

The correlations are mediated by various factors, such as social media access, cyberbullying, disrupted sleep, and dysfunctional family relationships, resulting in adult symptoms that diverge from conventional mental health indicators of depression and anxiety, potentially overlooked by studies employing standard screening tools. The symptoms of heightened hostility, disconnection from reality, and suicidal ideation might yield substantial societal repercussions as their prevalence escalates among younger generations.

“Based on these findings, and with the age of first smartphones now well under age 13 across the world, we urge policymakers to adopt a precautionary approach, similar to regulations on alcohol and tobacco, by restricting smartphone access for under 13s, mandating digital literacy education and enforcing corporate accountability.”

Since the early 2000s, smartphones have transformed the ways in which young individuals interact, acquire knowledge, and develop their identities. However, these opportunities are accompanied by increasing apprehensions regarding the potential of AI-driven social media algorithms to exacerbate undesirable content and promote social comparison, while also affecting other activities such as in-person interactions and sleep.

Despite numerous social media platforms establishing a minimum user age of 13, enforcement remains inconsistent. Simultaneously, the mean age of initial smartphone ownership is decreasing, as numerous children engage with their devices for several hours daily.

Presently, the global landscape regarding the prohibition of phones at educational institutions is varied. In recent years, numerous countries, including France, the Netherlands, Italy, and New Zealand, have prohibited or limited cell phone usage in institutions. The outcomes of these initiatives are constrained; nonetheless, a research commissioned by the Dutch government has identified enhanced concentration among pupils. This month, New York policymakers announced the state’s intention to become the largest in the U.S. to prohibit smartphones in schools, joining Alabama, Arkansas, Nebraska, North Dakota, Oklahoma, and West Virginia, all of which have enacted legislation mandating schools to implement policies that restrict smartphone access.

Previous research on screen time, social media, smartphone access, and other mental health outcomes has demonstrated predominantly detrimental consequences, while also presents varied and often contradictory findings, complicating the ability of politicians, educational institutions, and families to address this issue effectively. This may be related to the use of screeners that overlook the essential accompanying symptoms.

In this new analysis, the Sapien team utilised data from their Global Mind Project and employed the Mind Health Quotient (MHQ)—a self-assessment instrument that evaluates social, emotional, cognitive, and physical wellbeing—to provide a comprehensive ‘mind health’ score.

Their findings indicated that the symptoms most significantly associated with prior smartphone ownership are suicidal ideation, violence, dissociation from reality, and hallucinations. Young adults who acquired their first smartphone prior to age 13 exhibited diminished MHQ scores, with scores increasingly dropping as the age of initial ownership decreased. For instance, individuals who possessed a smartphone at age 13 achieved an average score of 30, whereas those who acquired one at age five got merely 1. 

The percentage of those classified as upset or struggling (indicated by scores reflecting five or more severe symptoms) increased by 9.5% for females and 7% for men. This pattern was uniform across all regions, cultures, and languages, indicating a crucial period of increased vulnerability. Furthermore, younger ownership correlates with reduced self-image, self-worth, and confidence, as well as diminished emotional resilience in females, and lower stability, calmness, self-worth, and empathy in males.

Subsequent study revealed that early access to social media accounts for around 40% of the correlation between early children smartphone ownership and later mental health, with detrimental family relationships (13%), cyberbullying (10%), and interrupted sleep (12%) also contributing significantly to the outcomes.

The researchers recognise that the COVID-19 pandemic may have exacerbated these patterns; nonetheless, the uniformity of these results across all worldwide areas indicates a more extensive developmental influence of early smartphone access.

Although existing research does not definitively establish direct connection between early smartphone ownership and subsequent mental health and well-being, the authors contend that the magnitude of possible harm is significant enough to warrant a preventive approach.

They advocate for policymakers to focus on four essential domains:

• Mandating education on digital literacy and mental health. 
• Enhancing the proactive identification of age violations on social media and ensuring significant repercussions for technology firms. 
• Limiting access to social media platforms. 
• Instituting graduated access restrictions for smartphones.

“Altogether, these policy recommendations aim to safeguard mind health during critical developmental windows,” Dr. Thiagarajan asserts that his research specialisation examines the influence of the environment on the brain and mind, with an emphasis on comprehending and facilitating the constructive growth of human cognition and systems.

“Their implementation requires substantial political and societal will, effective enforcement, and a multi-stakeholder approach, but successful precedents do exist. For example, in the United States, underage alcohol access and consumption is regulated through a combination of parental, commercial, and corporate accountability.”

She concludes: “Our evidence suggests childhood smartphone ownership, an early gateway into AI-powered digital environments, is profoundly diminishing mind health and wellbeing in adulthood with deep consequences for individual agency and societal flourishing.”

“I was initially surprised by how strong the results are. However when you give it due consideration, it does begin to make sense that the younger developing mind is more compromised by the online environment given their vulnerability and lack of worldly experience.”

“That said, I think it is also important to point out that smartphones and social media are not the only assault to mental health and crisis facing younger adults. It explains some of the overall decline but not all of it. Now, while more research is needed to unravel the causal mechanisms, waiting for irrefutable proof in the face of these population-level findings unfortunately risks missing the window for timely, preventative action.”

Original Publication
Authors: Tara C. Thiagarajan, Jennifer Jane Newson and Shailender Swaminathan.
Journal: Journal of Human Development and Capabilities
DOI: 10.1080/19452829.2025.2518313
Method of Research: Observational study
Subject of Research: People
Article Title: Protecting the Developing Mind in a Digital Age: A Global Policy Imperative
Article Publication Date: 21-Jul-2025