The debate about when to give a child their first smartphone has become an almost daily topic among parents, teachers, and pediatricians in recent years. While some emphasize practicality – safety, communication, and easier organization – others warn of the price children might pay during a period when the body and brain are changing rapidly. A new analysis published in the journal Pediatrics has further heightened concerns: children who already had their own smartphone by age 12 on average showed signs of depressive symptoms more frequently, more often had problems with lack of sleep, and had greater odds of obesity compared to peers without a phone.

It is important to immediately underline: the results speak of an association, not a proven cause-and-effect relationship. However, the sheer size of the sample and the way researchers approached the data give the topic new weight – providing both parents and experts with more concrete arguments for considering delaying the first “real” smartphone, as well as for setting clear rules when the phone eventually enters the child's daily life.

What the analysis of more than 10,000 children showed

A research team led by child psychiatrist Dr. Ran Barzilay from the Children's Hospital of Philadelphia (CHOP), in collaboration with researchers from the University of California, Berkeley and Columbia University, analyzed data from a large American longitudinal study of child development and the brain (ABCD). More than 10,000 participants from different parts of the USA took part in the analysis, and the key comparison was simple: do children at age 12 have their own smartphone or not – and how does this relate to three outcomes that are particularly sensitive in adolescence: mood, body weight, and sleep.

The results showed that smartphone ownership at age 12 is associated with greater odds of depressive symptoms, obesity, and insufficient sleep. The authors reported increased odds ratios – approximately 1.31 for depression, 1.40 for obesity, and 1.62 for insufficient sleep compared to peers without a phone. Such indicators do not tell what the absolute probability is that a problem will appear in an individual child, but they show that in a large group of children, smartphone ownership is connected with a greater burden on mental and physical health.

Even more sensitive was the question of the age at which the child first received a smartphone. Among children who already owned a device, an earlier age of first acquisition was associated with additionally higher odds of obesity and insufficient sleep. Researchers state that with every year of receiving a phone earlier, the odds for obesity (about 9%) and for insufficient sleep (about 8%) increase. In practical terms, the difference between getting a phone at 10 and at 12 years old, observed at the level of a large group, is not negligible.

The study also included changes over one year. Among children who did not have a smartphone at age 12, those who received it during the following year (by age 13) had higher odds of clinically significant psychological difficulties and insufficient sleep compared to peers who continued to remain without a phone. The authors emphasized that they do not claim the smartphone is “harmful for all children,” but that the decision needs to be made thoughtfully, weighing the benefits and risks, because for some families the phone solves real logistical and safety needs.

The analysis took into account numerous factors that can influence health: demographic and socioeconomic variables, pubertal development, parental monitoring, and ownership of other devices. Despite these adjustments, the associations remained present. But the researchers also clearly stated a limitation: they did not analyze what children do on the phone – which apps they use, how much time they spend on it, nor what content they consume. This means that this analysis does not give a direct answer to the question “which content is most problematic,” but points to a broader pattern associated with device ownership and the age of first acquisition.

For broader context, American media state that in this sample a significant portion of children already owned a smartphone, and the median age of first acquisition was around 11 years. This detail is important because it shows that the “race” for the first device often happens before high school – precisely in the period when key routines of sleeping, learning, and movement are being formed.

What children miss out on while the phone is constantly at hand

When discussing smartphones and children, the debate often comes down to fear of inappropriate content or dangerous contacts. This analysis, however, directs attention to a different problem: to what children are not doing while occupied with the screen for hours. In family conversations this sounds banal – “he is on the mobile too much” – but in everyday life, it translates into three areas that are the foundation of health in early adolescence: sleep, physical activity, and face-to-face socializing.

Claudia Allen, a clinical psychologist and director of the UVA Health Family Stress Clinic, warns that risks are often not created due to one app, but due to the “displacement principle”: time on the phone displaces movement, sleep, and live socializing. At an age when one learns how to manage emotions, build friendships, and adopt healthy routines, these three items act as basic protective factors – and when they weaken, problems with mood and physical health appear more easily.

Sleep: the foundation of development that is most easily disrupted

Guidelines for children's sleep are generally clear: children from 6 to 12 years need approximately 9 to 12 hours of sleep in 24 hours, and teenagers (13–18) about 8 to 10 hours. In practice, this is hard to achieve even without a smartphone, and a device in the bedroom further pushes boundaries – “just five more minutes” easily becomes half an hour or an hour, especially when apps send notifications, offer infinite scrolling, or encourage constant checking of messages.

Lack of sleep in children does not just mean fatigue. It is associated with poorer concentration, weaker regulation of emotions, and greater irritability, and consequently with poorer school performance and more frequent tensions in relationships. In the classroom, this can be seen as a drop in attention, harder learning, and more frequent conflicts with peers; at home as a “short fuse,” withdrawal, or sudden mood swings. In some children, “social fatigue” also appears: less patience for conversation, more impulsivity, and lower tolerance for frustration.

Sleep is also the physiological service of the organism: during the night, processes take place that influence metabolism, hunger and satiety hormones, and recovery. When sleep is systematically shortened, children more often reach for more caloric food, are less motivated for movement, and fall more easily into a cycle of sedentary behavior. This is one of the possible bridges between insufficient sleep and body weight, which can be “seen” at the group level in such analyses.

Movement: fewer playgrounds, more sitting

Children's physical activity is not just organized sports. It is also spontaneous movement: riding a bike, basketball on the playground, walking to a friend's, playing in the park, “roaming” around the neighborhood. When a smartphone is constantly at hand, a part of these activities loses the battle with the screen – not because children necessarily do not like movement, but because digital entertainment is available immediately, without leaving the house and without arranging with others. In a time when parents are already balancing between obligations and safety concerns, the phone becomes the “quietest” form of entertainment, but also the easiest path to long-term sitting.

Precisely for this reason, experts often do not speak only about banning, but about restoring balance. If a child gets a phone, there should be clear periods without screens, especially before sleep and during the day when movement would naturally be expected. Without such rules, the phone becomes the easiest way to fill a void – and the body and mood pay the price.

Socializing live: skills learned only “in reality”

The third element that is often underestimated is face-to-face socialization. Early adolescents learn how to start a conversation, how to react to disagreement, how to read non-verbal signals, and how to deal with rejection. These are skills that are not learned through a “like,” but through real situations at school, on the playground, and in the neighborhood – through conflict, reconciliation, humor, awkwardness, and empathy.

The experience of the pandemic period showed how much isolation and reduced contacts can affect children: some of them had a harder time joining in after returning to classrooms, had more anxiety and insecurity in social situations. If the phone becomes a permanent substitute for live socializing, there is a risk that social “training” will become sparse – and that children in a sensitive age will enter high school with less experience in resolving conflicts, meeting new people, and building friendships.

Allen warns in this context also about the reality of digital platforms: many are designed to encourage frequent returns (notifications, “streaks,” personalized content recommendations), so self-control is harder than parents sometimes expect from an eleven-year-old. Therefore, the question “why can't they just turn it off” often misses the point – children need clear rules and adults who will consistently enforce them, with an explanation that limits are set for the sake of health, not for the sake of punishment.

Why the threshold around age 12 is particularly sensitive

The age from 11 to 13 years in most children coincides with sudden changes: puberty, strengthening of the need for belonging to a peer group, greater sensitivity to comparison, and stronger emotional waves. At the same time, school obligations become more complex, and days are often overcrowded. In this context, a smartphone is not a neutral object, but a strong amplifier of habits – both good and bad. It increases the availability of information and communication, but also the availability of distractions, comparison, and conflicts that continue even after the school bell.

For some families, a phone can indeed be useful: communication with parents, navigation, arrangement regarding training, access to educational content, and even maintaining friendships when children are physically distant. But the question is when and how we introduce it. If the device arrives before basic routines of sleeping, learning, and movement are developed, there is a greater chance that it will “latch onto” precisely the weakest points – late at night, during homework, or in moments of boredom. In practice, this often means: the child gets the device “for safety,” and soon the majority of time turns into content and apps that have nothing to do with either safety or logistics.

Experts therefore increasingly emphasize that parents should not perceive the smartphone as a one-time event (“we gave it – and that's it”), but as a process that is constantly adapted. Rules that apply in the fifth grade do not necessarily have to apply in the seventh, but the principle remains the same: the phone must not take over basic life needs. Parental monitoring in this sense is not the same as spying – it is setting a framework, checking the routine, and readiness for conversation when problems appear.

What parents can do as early as today

The parental dilemma is often simple in theory, but difficult in practice: “Everyone in the class already has a phone – will I isolate my child?” Peer pressure is real and many parents do not want to be the only ones saying “no”. This is precisely why there is increasing talk about solutions that do not start from perfectionism, but from agreement and structure – both within the family and among parents in the class.

1) Delaying the smartphone, but not communication

One of the compromises that many families choose is delaying the smartphone, with an alternative like a basic mobile phone for calls and texts or a smartwatch without social networks. This solves the practical part (contact and safety), and reduces the risk that the child enters the world of apps that compete for attention too early. In families where a phone is “necessary” due to logistics, such a step often gives parents time to set rules in peace, and the child to develop routines before receiving the full package of digital challenges.

2) Rules before the device: family “contract” on the screen

If a child gets a smartphone, rules are easier to set before habits become ingrained. A written family agreement is often recommended: when the phone is used, where it charges (ideally outside the bedroom), what is forbidden during school and homework, and how conflicts over the screen are resolved. It is useful that rules apply to adults as well – because children notice double standards very quickly, and the best message is the one seen in parents' behavior.

• Phone outside the bedroom or at least a strict screen “curfew” 60–90 minutes before sleep, with charging the device in the living room or kitchen.


• No phones at the table and during shared time, so that conversation remains a habit, not an exception.


• Limits for social networks, especially in early adolescence, with conversation about pressure, comparison, and online conflicts.


• After school first movement and obligations, and only then screen, so that physical activity is “locked” into the schedule.


• Regular routine checks: sleep, school, attitude towards obligations, and mood – because changes often first “surface” in these areas.

A practical tool that can help parents in setting such rules is also the online family media use plan (for example AAP Family Media Plan), which helps screens fit into family goals, rather than suppress them. In practice, this means: sleep and school have priority, movement is planned, and “free screen time” becomes clearly defined. At the same time, parents can adjust privacy, age restrictions, and app limitations, and monitor whether the child's routine changes after the introduction of the phone.

3) Agreement with other parents: when pressure becomes a collective problem

One of the useful approaches is to try to solve the problem together. If several families in the class or generation agree that they will delay the smartphone until a certain age, the “everyone has one” pressure weakens abruptly. In the USA, there are initiatives like Wait Until 8th, which are based on the logic of a joint promise: parents publicly commit to a delay, so children do not feel they are “singled out”. Even without a formal movement, a similar effect can be achieved by agreement within the class – with a simple idea: it is easier to endure a boundary when the boundary is shared.

Such an approach does not solve everything, but it gives parents much-needed support in consistency. To children, meanwhile, it sends a clear message that delay is not a punishment, but a joint agreement focused on health: enough sleep, enough movement, and enough live relationships. When a child knows they are not the only one without a smartphone, it is easier to withstand pressure and the feeling of being “out of the crew” is created less.

4) Zones without screens and school consistency

In many schools around the world, limiting mobile phones during classes and breaks is being discussed, because the device affects not only the individual child but the entire class dynamics. The rule “phone in the bag” makes sense only if it is enforced consistently and if the school clearly communicates expectations to parents. In the family, a similar principle can be applied through “zones without screens” – for example, the kitchen and dining room – or through an agreement that phones are charged in one place, outside of children's rooms.

For parents who want an additional framework, the habit of introducing regular “tech-free” periods (an hour before sleep, meal times, study time) and encouraging live socializing as an equally important part of the child's routine can also help. If a parent notices that the child has started to be chronically sleep-deprived, avoids movement, or withdraws from real relationships, that is a signal for a change of rules: moving the phone from the bedroom, shortening screen time, turning off notifications, deleting certain apps, or arranging a “digital vacation” during the week – with conversation and clear reasons, and not “just because”.