Getting enough protein in our food is crucial for health and development. When we are still growing this protein is especially important. In this study, we looked at how inadequate dietary protein affects brain function both when rats were adults and during their adolescence. We used a recording technique called fast-scan cyclic voltammetry, and saw that low protein diets affected the release of dopamine, an essential neurotransmitter for motivation and learning. Interestingly, the consequence of the low protein diet differed depending on the age of the rats and had stronger effects in adolescent animals than in adults. This research, led by Fabien Naneix and published as an Open Access paper in Neuropsychopharmacology, highlights the vulnerability of the brain to dietary deficiencies during development.