Study analysis · Nutrition research · 2025
Teens in Costa Rica are eating MORE ultra-processed snacks than traditional meals—and it’s the wealthier, urban girls doing it most.
The more snack foods like chips and soda Costa Rican teens eat, the less they eat beans, rice, and other healthy traditional foods.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
In simple terms
This study looked at what kids in one city in Costa Rica ate in a few days and found that kids who ate more junk food also ate less of their traditional healthy foods. But it didn’t watch them over time, so we don’t know if the junk food caused the bad diet or if kids who already liked less healthy food just ate more junk.
What’s the bottom line?
This study looked at what kids in Costa Rica eat and found that the more snacks like chips and soda they eat, the less they eat healthy traditional foods like beans and rice.
How strong is this study?
The study asked a lot of kids what they ate and used good methods to count the food, which makes it reliable for describing what’s happening right now. But because it didn’t follow kids over time or control for everything that could affect their diet, we can’t be sure the results mean one thing causes another — so we should be careful trusting big claims.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
25 / 100
- Randomizationnot randomized
- Blindingblinding unclear
- Control groupno control group
- Sample size (n=818)+19.7/20
- Follow-upno follow-up reported
100 / 100
77 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 544 / 100
Probability of being correct
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
This design cannot establish causation — the findings describe an association, not a cause. This is a cross-sectional study, which measures exposure and outcome at the same time, making it impossible to determine whether ultra-processed food intake preceded changes in dietary patterns or vice versa. Temporal sequence cannot be established, and confounding factors (e.g., socioeconomic status, lifestyle) may explain the observed associations.
Minor COI
Minor conflicts that may slightly influence the study
Study was funded by government health agencies and a non-profit heart association; no industry funding or direct author employment by funders, but one author received scholarships from Mexican and Harvard institutions, which may represent minor non-financial support.
Funders
Conflict Details
Mexican Council of Science and Technology (CONACYT): Received scholarships to facilitate research
Fundación México en Harvard: Received scholarships to facilitate research
Harvard University: Received scholarships to facilitate research
Costa Rican Ministry of Health: Funding acquisition for the study
American Heart Association (AHA): Funding acquisition for the study
No conflict of interest statement was provided, but funding sources are government and non-profit entities. Author scholarships from academic institutions do not indicate industry ties or direct financial stake in study outcomes. No evidence of funder influence on study design, analysis, or publication.
Key takeaways
- 01
Kids ate 35.9% of their calories from ultra-processed snacks, mostly in the morning.
- 02
For every 10% more snack food they ate, their healthy diet score dropped by 0.44 points.
- 03
High snack eaters got 43.9% of calories from UPF; low snack eaters got only 29.9%.
- 04
Yes — this means kids eating lots of snacks are missing out on important nutrients and eating less of the healthy foods their culture traditionally values.
Surprising findings
- Higher socioeconomic status correlated with higher UPF intake, not lower.Globally, UPF consumption is typically higher in low-income groups due to affordability and accessibility. Here, wealthier, urban teens are the biggest consumers—suggesting cultural prestige or marketing influence.
- Morning snacks were the biggest driver of UPF consumption (58.5%).Most assume lunch or after-school snacks are the problem—but in Costa Rica, the morning snack (likely at school) is the epicenter of ultra-processed food intake.
Practical takeaways
Pack a traditional Costa Rican-style breakfast (beans, plantains, fresh fruit) instead of letting teens grab packaged snacks at school.
This study only shows correlation—not causation—and results may not apply to other countries or cultures.
medium confidenceIf you live in an urban, middle- or upper-income household, audit your teen’s morning snacks—UPF may be sneakily replacing cultural foods.
The study was limited to San José; rural or lower-income teens may have different patterns.
medium confidenceWhy this study matters
Snacks Are Stealing the Traditional Diet
Ultra-processed foods (UPF) made up 35.9% of teens’ total daily calories, with 58.5% of that intake happening during morning snacks. Teens with the lowest adherence to the traditional Costa Rican diet got 43.9% of their calories from UPF—nearly half their diet.
This flips the script: it’s not just poor kids eating junk food—it’s wealthier, urban teens abandoning their cultural diet for snacks, making it a class and culture issue, not just an income one.
Girls, Cities, and Richer Families Eat More Junk
UPF consumption was significantly higher among females, urban residents, and adolescents from higher socioeconomic status groups—contrary to the global norm where lower-income groups often consume more ultra-processed foods.
This challenges the assumption that junk food is a poverty problem. Here, affluence and urbanization are linked to dietary decline—making it a cultural shift, not just an economic one.
Every 10% More Snacks = Worse Diet Score
Each 10-percentage-point increase in UPF energy intake was linked to a 0.44-point drop in the Traditional Costa Rica Adolescents Diet Score (TCRAD)—a statistically strong and consistent association (P < .0001).
This isn’t just ‘eating more junk’—it’s a measurable erosion of cultural dietary identity. The effect size is large enough to predict real health consequences over time.
Want the whole report?
Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.
Standing
Who’s using this study?
The videos and claims on this site that lean on this study, and the researchers who wrote it.
1 video from Physionic cite this study, drawing 1 claim from it.
- Correlational evidence
The evidence shows a real association, but the studies are observational, so they cannot prove cause and effect. Stronger studies could still change the picture.
Evidence