Smartphone addiction in adults: is it really 1 in 3?

A German study published this month says about one in three adults use their phone in an "addiction-like" way, and more than half of 18 to 29 year olds do. If you searched for smartphone addiction in adults after seeing that headline, the short answer is this: about a third of adults scored high on a questionnaire about phone use. That is a long way from a third of adults being diagnosed with anything.

The numbers are still worth reading, especially if you are under 30. Below is what the study measured, why the word "addicted" overreaches, what a second study from Hungary says separates problem use from plain heavy use, and a few changes that follow from the evidence.

What the German study measured: questionnaires plus two weeks of tracking

About 1,300 adults aged 18 to 65 took part, according to the report by BR, republished by RTÉ. They filled in questionnaires on phone use and mental health at the start and end, an app tracked their phone use for about two weeks, and the team used AI in the analysis.

Overall, 32% of men and 29% of women showed problematic smartphone use. Average screen-on time was just under 4.5 hours a day, mostly in the evenings. That comes to over 30 hours a week, which psychologist Boris Gauß called "a pretty good part-time job."

About a fifth of participants said their phone use affected their concentration and health. The most common complaints were neck and back pain, poor concentration and memory problems. The team says anxiety and depression "could be linked" to extreme use, which describes an association. It does not show the phone caused either.

Why smartphone addiction in adults is the wrong label for this study

The authors themselves stress that their figures are not a clinical diagnosis. They come from questionnaire scores. I also could not find the primary report, so the questionnaire's cutoff score and whether the sample represents German adults as a whole are still unknown.

There is a funding detail worth knowing too. The project, called KiQuNu, is funded by Germany's Federal Ministry for Economic Affairs. Gauß works for detoxi Health GmbH, which took part and eventually aims to build an app that rates users' risk. That does not make the findings wrong, but a company with a product in mind has an interest in the problem looking big.

A more accurate term is problematic smartphone use, which is the phrase researchers tend to use, including the Hungarian team below. It describes a pattern that causes trouble without implying a medical condition.

More than half of 18 to 29 year olds scored in the problem range

That is a steep slope by age. It suggests younger adults use their phones more, or differently, in ways that show up on these questionnaires.

What it does not prove is that phones harm young adults more. This is a snapshot, so the gap could reflect life stage (students and new workers live on their phones for practical reasons) or simply how different age groups answer questions about themselves.

What you do on the phone separated the problem group from everyone else

A study from Semmelweis University in Budapest, covered by ScienceDaily and published in Acta Psychologica in 2025, looked at students aged 18 to 35. They filled in online questionnaires, did cognitive tests and had physical measurements taken. The researchers found three patterns:

• Pure social: mostly using the phone to communicate with people.
• Light process: under about 4 to 5 hours a day on a mix of activities.
• Heavy process: about a third of participants, 4 to 5 or more hours a day, mostly consuming content.

The heavy group did worse than expected for their age on memory and attention tests. They also reported poorer sleep, more craving for constant stimulation and more trouble resisting the urge to check their phones. The people who mainly talked to friends were a separate group.

Two caveats. The data was collected at one point in time, and the release says plainly that the results do not show scrolling causes these differences. And the split was partial: what people did mattered most for thinking skills, while total time mattered more for physical effects like "text neck" (head tilted forward), which may affect balance and reaction time.

Self-control and FoMO predicted problem use better than personality

Neuroticism, a tendency toward anxiety and low mood, did not predict problematic use on its own. Weak self-control and fear of missing out did. Lead researcher Johanna Takács says people prone to negative emotions "do not automatically become addicted."

I find that reassuring. Your temperament is hard to change, but the habit of checking and the itch of FoMO are things you can put friction around.

128 notifications a day breaks attention into small pieces

Those busiest hours overlap with the working and study day. Gauß estimates it takes about 10 minutes to regain focus after each distraction, but that is his own claim, so treat it as an opinion. The 128 figure is the measured part, and it is a lot of interruptions.

Am I addicted to my phone? A three-question check and seven changes

These questions mirror what the Semmelweis questionnaire asked. If you want a longer list focused on social apps, I have a separate checklist of social media addiction signs.

• Do I miss things I planned because of my phone?
• Do I think about my phone when I'm not using it?
• Is most of my phone time spent consuming content rather than talking to people?

1. 01
   Check your real number

   open your weekly Screen Time or Digital Wellbeing figure and compare the daily average with the roughly 4.5 hours in the German study.

2. 02
   Sort your hours

   split time spent talking to people from time spent consuming content, since the Hungarian problem group was defined by the second.

3. 03
   Cut the feed and keep the messages

   remove or block endless feeds like Reels, Shorts and For You, and leave messaging apps alone.

4. 04
   Silence social alerts and batch the rest

   turn off notifications from social apps and check messages at set times, which was the Semmelweis team's first suggestion.

5. 05
   Put friction in front of FoMO

   set fixed check-in times, add a small pause before opening an app, and remind yourself you can catch up later.

6. 06
   Protect your evenings

   use in the German study peaked in the evening, and the heavy group in Hungary reported poorer sleep.

7. 07
   Raise the phone and move more

   hold it nearer eye level to ease forward head posture, and add exercise, as the researchers suggest.

For the evening part, I've written about how to stop scrolling in bed without relying on willpower, and about blocking Reels while keeping Instagram on an iPhone.

If cutting back keeps failing, talk to a GP or therapist

If you have tried to cut back several times and can't, or your phone use comes with anxiety or low mood, it is worth raising with a GP or a therapist. You don't need to call yourself an addict to ask for help with a habit that is getting in the way.