Plant protein substitution associated with academic performance in Spanish adolescents

Researchers conducted a secondary analysis of the Eating Healthy and Daily Life Activities (EHDLA) study, including 769 adolescents aged 12–17 years; 55.5% were girls. Dietary intake was assessed with a 45-item food-frequency questionnaire, and academic performance was measured using grade point average and grades in language, mathematics and foreign language. Robust linear regression models estimated associations with isocaloric substitution of animal-based protein by plant-based protein, adjusting for sociodemographic, lifestyle and anthropometric factors.

Modeled replacement of animal protein with plant protein was associated with higher scores across all academic outcomes (all p<0.001). Substitution equal to 5% of total energy intake was associated with higher grade point average and subject-specific scores. The associations were reported as being driven primarily by replacing protein from red or processed meat and certain fish with plant-based sources.

The findings are observational and show associations, not evidence that protein substitution causes improved academic performance. Dietary intake was self-reported, and the analysis cannot rule out residual confounding or establish the effect of changing diet. The results do not support a specific clinical recommendation to alter adolescents’ diets for academic benefit.