According to Gram Research analysis, Swedish teenagers leave school grounds for about 21% of their meals during school hours, and these outside meals are significantly less healthy than school lunches. A 2026 study of 483 Stockholm students found that 65% of meals purchased outside school were unhealthy compared to 43% of school meals, with outside eating dominated by sugary snacks and sweetened beverages rather than balanced meals with vegetables and protein.
A new study of Swedish teenagers found that one in five meals eaten during school hours happen outside school grounds, and those outside meals are much less healthy. Researchers tracked what 483 students in Stockholm ate over four years using phone photos and GPS data. They discovered that meals eaten at school included more vegetables and balanced nutrition, while food bought from nearby shops was mostly unhealthy snacks and sugary drinks. Even though schools offer free healthy lunches, many teens choose to leave campus to buy less nutritious food instead.
Key Statistics
A 2026 cross-sectional study of 483 Swedish adolescents found that 21% of meals and drinks consumed during school hours were purchased outside school grounds, with 65% of these outside meals classified as unhealthy compared to 43% of school meals.
Research from Stockholm schools showed that meals eaten at school contained significantly higher proportions of vegetables, fish, and seafood, while meals purchased outside school were more often snack-based and included sweetened beverages at much higher rates.
Among 4,562 food images analyzed in the Swedish study, the proportion of unhealthy meals was 22 percentage points higher outside school (65%) than inside school (43%), a statistically significant difference indicating the school food environment supports healthier choices.
The Quick Take
- What they studied: What Swedish teenagers eat during school hours, including whether they eat at school or leave to buy food elsewhere, and how healthy those food choices are
- Who participated: 483 students aged 13 to 19 years old from two schools in central Stockholm, Sweden, studied over four years from 2019 to 2021 and again in 2024
- Key finding: About 21% of meals and drinks consumed during school hours were purchased outside school grounds, and these outside meals were significantly less healthy (65% unhealthy) compared to school meals (43% unhealthy)
- What it means for you: Even when schools provide free healthy lunches, many teenagers choose to leave campus and buy unhealthy snacks and fast food instead. This suggests that simply offering healthy food at school may not be enough to change eating habits without additional strategies to make healthy choices more appealing or convenient.
The Research Details
Researchers conducted a repeated cross-sectional study, which means they collected data from different groups of students at different time points over four years. This approach allows researchers to see how eating patterns change over time without following the same students throughout. Students used special mobile apps to take pictures of their meals and drinks, and the app recorded where they were eating using GPS technology (location tracking). The researchers then looked at all 4,562 photos collected and manually reviewed each one to determine what foods were eaten and whether they were healthy or unhealthy choices.
The study focused on students in central Stockholm, an area with many fast-food restaurants and snack shops nearby. This location was chosen specifically because it represents a real-world environment where teenagers have easy access to unhealthy food options outside of school. By studying students in this setting, researchers could understand how the availability of junk food influences eating choices when students leave school grounds.
The data collection happened during school hours, meaning researchers only looked at what students ate while school was in session. This approach helped isolate the effect of the school food environment and student choices during the school day, rather than looking at all eating throughout the entire day.
Understanding where and what teenagers eat during school hours is important because eating habits formed during adolescence tend to continue into adulthood. If teenagers develop a preference for unhealthy fast food and snacks during their school years, they may maintain these habits as adults, leading to higher rates of obesity, diabetes, and heart disease. This study provides real-world evidence about how teenagers actually behave around food, not just what they say they eat. By using photos and GPS data, researchers captured actual eating patterns rather than relying on memory or self-reporting, which can be inaccurate.
This study has several strengths that make its findings reliable. The large number of photos (4,562 images) provides a substantial amount of real-world data. The use of GPS-tagged pictures and manual review of images reduces the chance of inaccurate reporting compared to asking students to remember what they ate. The study was repeated over multiple years, which helps confirm that the patterns are consistent and not just a one-time observation. However, the study only included students from two schools in one city in Sweden, so the results may not apply to teenagers in other countries or less urban areas. Additionally, students had to voluntarily participate and use the app, which means the sample may not represent all teenagers equally.
What the Results Show
The most striking finding was that 21% of all meals and drinks consumed during school hours were purchased outside school grounds. This means that roughly one in every five eating occasions happened away from school, despite schools offering free meals. The quality difference between school meals and outside meals was dramatic: 65% of meals bought outside school were classified as unhealthy, compared to only 43% of meals eaten at school. This 22 percentage point difference was statistically significant, meaning it was not due to chance.
When students ate at school, their meals were more likely to be complete, balanced meals with multiple components like protein, vegetables, and grains. School meals contained significantly higher amounts of vegetables, fish, seafood, and red meat compared to outside meals. In contrast, meals purchased outside school were typically snack-based, meaning they consisted of single items like chips, candy, or fast food rather than balanced meals with different food groups.
Sweetened beverages were a major concern in outside meals. Both sugar-sweetened drinks (like soda) and artificially sweetened drinks (like diet soda) were consumed much more frequently when students ate outside school compared to at school. This pattern suggests that students buying food from nearby retailers are making choices that are high in added sugars or artificial sweeteners, which can contribute to weight gain and other health problems.
The study revealed that the school food environment itself appears to support healthier choices. Even though some unhealthy meals were consumed at school (43%), the school setting provided structure and nutritional standards that resulted in better overall meal quality. The fact that students actively chose to leave school to purchase less healthy food suggests that factors beyond just food availability influence eating choices. These factors might include peer influence, desire for independence, taste preferences, or the appeal of fast-food marketing. The high density of fast-food retailers near the schools in central Stockholm appeared to make it easy and convenient for students to purchase unhealthy options, which may have encouraged this behavior.
This study builds on existing research showing that school meals are generally more nutritious than food purchased elsewhere. Previous studies have documented that adolescents’ eating habits established during school years tend to persist into adulthood, making this a critical period for intervention. The finding that students actively leave school to purchase unhealthy food aligns with other research showing that convenience and peer influence are major drivers of adolescent food choices. However, this study provides new evidence using real-world photo documentation rather than relying solely on self-reported dietary recalls, which strengthens the reliability of the findings. The GPS-tagged approach is innovative and provides more accurate location data than previous studies.
The study only included students from two schools in central Stockholm, Sweden, so the results may not apply to teenagers in rural areas, smaller cities, or other countries with different food cultures and school systems. Students who participated had to use a mobile app and take pictures of their food, which means the sample may have been biased toward students who were more tech-savvy or motivated to participate. The study did not collect information about why students chose to leave school or what factors influenced their food choices, so we cannot determine the reasons behind the behavior. Additionally, the study relied on manual review of photos to classify meals as healthy or unhealthy, which introduces some subjectivity even though researchers likely used consistent criteria. The study did not account for individual factors like family income, cultural background, or personal health conditions that might influence eating patterns.
The Bottom Line
Schools should consider strategies beyond simply offering free healthy meals, such as making the school cafeteria more appealing, involving students in menu planning, or restricting student access to leave campus during lunch periods. Communities should work to limit the density of fast-food retailers near schools or implement policies that encourage healthier food options in nearby shops. Parents and educators should discuss with teenagers why healthy eating matters and help them understand the long-term health consequences of frequent consumption of unhealthy snacks and sugary drinks. These recommendations are supported by moderate to strong evidence from this study and align with public health guidelines.
School administrators, teachers, parents, and policymakers should care about these findings because they affect the health of teenagers. Teenagers themselves should understand how their food choices during school hours can influence their long-term health. Public health officials should use this information to develop interventions targeting adolescent eating patterns. However, this study specifically examined Swedish teenagers in an urban setting, so the exact recommendations may need adjustment for different populations or geographic areas.
Changes in eating habits typically take several weeks to months to become established. If schools and communities implement interventions to encourage healthier eating, researchers would expect to see measurable improvements in dietary patterns within one to three months. However, long-term health benefits like weight loss or improved metabolic markers may take several months to a year to become apparent. Sustained behavior change often requires ongoing reinforcement and support over many months or years.
Frequently Asked Questions
Do teenagers eat healthier food at school or when they buy food outside school?
Teenagers eat significantly healthier food at school. A 2026 Swedish study found that 65% of meals purchased outside school were unhealthy compared to only 43% of school meals, with outside meals being mostly snacks and sugary drinks rather than balanced meals with vegetables.
What percentage of school meals do teenagers buy outside school?
About 21% of meals and drinks consumed during school hours are purchased outside school grounds. This means roughly one in five eating occasions during the school day happens away from school, despite free healthy lunches being available.
Why do teenagers leave school to buy unhealthy food if free lunches are available?
The study did not directly measure why students leave school, but the high density of nearby fast-food retailers, peer influence, desire for independence, and taste preferences likely play roles. Simply offering healthy food may not be enough without addressing these underlying factors.
What types of foods do teenagers buy when they leave school?
Teenagers buying food outside school primarily purchase snack-based meals high in sugar and unhealthy fats, including sweetened beverages, fast food, and candy. These meals lack the vegetables, protein, and balanced nutrition found in school lunches.
Can eating habits during school years affect health as an adult?
Yes, research shows that eating habits established during adolescence tend to persist into adulthood and influence long-term health outcomes. Teenagers who frequently consume unhealthy snacks and fast food may continue these patterns as adults, increasing disease risk.
Want to Apply This Research?
- Users can photograph meals and snacks during school hours and note the location (at school or outside school) to track their own eating patterns. Over one to two weeks, this creates a visual record showing what proportion of meals are consumed outside school and how the nutritional quality differs between locations.
- Set a specific goal such as eating school lunch at least four out of five school days, or limiting outside purchases to one day per week. Use the app to log each meal location and rate its healthiness on a simple scale, creating accountability and awareness of eating patterns.
- Track the percentage of meals eaten at school versus outside school on a weekly basis. Monitor the types of foods purchased outside school and set gradual goals to replace unhealthy snacks with healthier options. Review photos monthly to identify patterns and adjust strategies as needed.
This research describes eating patterns among Swedish teenagers and should not be interpreted as medical advice. Individual nutritional needs vary based on age, activity level, health conditions, and other factors. Parents, educators, and teenagers should consult with healthcare providers or registered dietitians for personalized nutrition guidance. While this study provides valuable insights into adolescent eating behaviors, results from Swedish schools may not directly apply to all populations or geographic regions. Any changes to school food policies or individual dietary practices should be made thoughtfully and in consultation with appropriate professionals.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.