Ultra-processed foods undermine diet quality in Mediterranean youth, study shows

From Egypt to Italy, children who regularly eat ultra-processed foods are falling short of dietary guidelines and moving away from traditional Mediterranean eating patterns, researchers warn.

In a recent article published in the journal Foods, researchers examined the consumption of unhealthy ultra-processed foods (UPFs) among children and adolescents in five Mediterranean countries, exploring how UPF intake relates to diet quality.

Their analysis showed that higher consumption of UPFs was linked with poorer overall diet quality, reduced compliance with dietary guidelines, and lower adherence to the Mediterranean diet.

Background

In recent decades, diets have shifted from seasonal, fresh, local foods toward industrially processed alternatives, a trend especially evident among children and adolescents.

Technological advances and globalization have reshaped food production, increasing shelf life and convenience but often sacrificing nutritional quality. This shift raises concerns, as children are particularly vulnerable due to developmental needs, marketing susceptibility, and reliance on caregivers and schools for diet.

Early exposure to poor eating habits can disrupt healthy growth, impair cognitive and immune function, and increase the long-term risk of cardiovascular disease, obesity, and diabetes.

Mediterranean countries, once known for the balanced and nutrient-rich Mediterranean diet, are also experiencing a gradual move toward Western-style eating, marked by nutrient-poor, calorie-dense foods. Although overall consumption of such foods remains lower than in countries like the US or UK, these trends are concerning.

According to the Nova classification, UPFs are industrial products high in sugars, fats, and additives but low in essential nutrients. Growing evidence links frequent UPF consumption with poor diet quality, chronic diseases, and even cognitive problems.

About the Study

Researchers analyzed dietary habits of children and adolescents aged between 6 and 17 years in five Mediterranean countries, namely Lebanon, Egypt, Portugal, Spain, and Italy, using data provided by 2011 parents recruited from a consumer database.

Eligible participants had to be parents of children within the age range and have internet access, and data, including demographic information, were collected via an online survey. Weight status was calculated using established growth chart body mass index (BMI) percentiles, classifying participants as obese, overweight, or normal weight.

Physical activity was assessed using a questionnaire, which categorized activity as low, moderate, or high. Dietary intake was assessed through 24-hour recalls and weekly food frequency questions. Special attention was given to 13 categories of UPFs, including fast food, soft drinks, pastries, and candies. UPF consumption was categorized as “high” (above the median) or “daily” (daily consumption of at least one type of UPF; not necessarily all categories).

Diet quality was assessed using two indices: the Youth Healthy Eating Index (adapted to a maximum score of 90 in this study) and the Mediterranean Diet Quality Index (with a high score of 12). Statistical analyses included Chi-square, analysis of variance (ANOVA), and multivariate logistic regression, adjusting for physical activity, weight, age, and sex.

Key Findings

Among the 2011 participants, no significant differences by sex were found across UPF consumption groups. However, obesity and overweight were more common among children with higher daily UPF intake. Interestingly, a higher proportion of physically active adolescents also reported high UPF consumption. The authors proposed this might reflect increased hunger from higher activity rather than inherently unhealthy behaviors, but noted this contrasts with most literature and requires confirmation.

In terms of food groups, high and daily UPF consumers ate more sweets, nuts, dairy, meat, and cereals, but showed a lower proportion consuming high fruit intake (≥3 portions/day) and a higher proportion consuming moderate fruit (1–2 portions/day), with Spain as a notable exception where high UPF consumers ate more fruit. Importantly, vegetable and whole grain intake remained consistent regardless of UPF consumption levels. Country-specific patterns largely mirrored these results.

Diet quality was consistently lower in children with higher UPF intake. Those consuming UPFs daily or frequently scored significantly lower on both the diet quality indices. For example, daily UPF consumption was associated with about 40–60% lower odds of achieving high diet quality scores. Subgroup analyses showed particularly strong negative associations in Egypt, Portugal, and Italy, while Lebanon showed paradoxical increases in Mediterranean diet adherence among high UPF consumers, and findings were less consistent in Spain.

Further analysis showed that high UPF consumers were less likely to meet dietary recommendations for fats, sweets, meat, and legumes across countries. Some exceptions were noted, such as higher adherence to Spanish guidelines for fish among frequent UPF consumers.

Conclusions

This study found that higher consumption of unhealthy UPFs among children and adolescents in Mediterranean countries was strongly linked with poorer diet quality and lower adherence to the Mediterranean diet, echoing evidence from other research.

Although some country-level variations emerged, frequent UPF intake was associated with unbalanced diets rich in fats, sweets, and processed meats, potentially displacing minimally processed foods. The study provides a comprehensive multi-country assessment of UPF consumption in Mediterranean youth using standardized metrics.

The study’s strengths include its standardized, multi-country design and focus on both diet quality indices and adherence to national guidelines. However, limitations include its cross-sectional design, reliance on parental reports (which may consist of recall and social desirability bias), and restricted focus on only certain UPF categories.

In conclusion, reducing unhealthy UPF intake is essential to preserve the health benefits associated with the Mediterranean diet. This requires multi-sectoral strategies, including education, stricter marketing regulations, school nutrition policies, and industry accountability through reformulation and labeling.