October 14, 2024 — A recent study published in Pediatric Research has explored the potential of the Mediterranean diet to curb childhood obesity and overweight. While the findings show some benefits, researchers note that the effects are modest and lose statistical significance after adjusting for certain factors.
Background
Childhood obesity is a global public health crisis, with rates escalating rapidly in many countries. In Spain, where this study was conducted, over 41% of children aged six to nine are overweight, and 17% are considered obese. This issue often persists into adolescence and adulthood, with estimates suggesting that 55% of obese children remain obese as teenagers, and 80% of obese adolescents carry the condition into adulthood.
Several factors contribute to childhood obesity, including behavioral, environmental, and genetic influences. Unhealthy diets and physical inactivity are primary drivers, particularly in children. In response, researchers have been investigating how specific dietary patterns, such as the Mediterranean diet, could help manage weight.
The Mediterranean diet is renowned for its balance of fibers, antioxidants, healthy fats, and plant-based proteins. It has been linked to a lower risk of various health conditions, including cardiovascular diseases and diabetes. In children, there is some evidence that it may also reduce body mass index (BMI), but more studies are needed to understand its full impact on childhood weight management.
The Study
The study examined 1,389 children aged eight to ten from four municipalities in Spain between 2012 and 2014, with follow-ups 15 months later. Researchers assessed the children’s adherence to the Mediterranean diet using a validated questionnaire and measured their waist circumference, height, and weight to calculate standardized BMI (zBMI). A zBMI score greater than one standard deviation was categorized as overweight, while a score greater than two was considered obese.
Other factors, such as physical activity, screen time, and socioeconomic status (based on maternal education), were also taken into account to better understand the relationships between diet and weight.
Findings
At the start of the study, about 41% of children had high adherence to the Mediterranean diet, and nearly half had moderate adherence. During the study, adherence to the diet decreased, as did zBMI. However, physical activity and screen time increased, contributing to fluctuations in BMI.
Certain Mediterranean foods were found to have protective effects against large increases in zBMI. For instance, consuming nuts two or three times per week and eating yogurt, cheese, or vegetables daily was associated with a lower risk of significant weight gain. Despite this, the overall effect size was small, and the results lost statistical significance when researchers adjusted for baseline zBMI.
Researchers found that children with medium to high adherence to the Mediterranean diet at the beginning of the study were less likely to experience large increases in zBMI. However, after accounting for initial zBMI levels, the association weakened. No significant relationship was observed between adherence to the diet and new cases of excessive weight gain during the study.
Conclusion
While previous studies have suggested that the Mediterranean diet could help reduce BMI in children, this study’s findings indicate that the effect is modest. Certain Mediterranean foods may offer some protection against large weight increases, but the overall impact is limited.
The study’s authors acknowledge several limitations, including the reliance on self-reported dietary data, which may introduce biases. They also highlight the need for more comprehensive research that considers energy intake and additional socioeconomic factors.
Ultimately, while the Mediterranean diet may offer some benefits for childhood weight management, more long-term, high-quality studies are required to provide stronger evidence and guide public health recommendations.