A randomized crossover study was carried out in three University accommodation halls. Participants consumed either beef (Pirenaica breed) (PB) or conventional chicken (CC) three times per week for an 8-week periods with their usual diet, each one separated by a 5-week wash out period. Dietary variables were recollected by the Food Frequency Questionnaire (FFQ), and the Diet Quality Index (DQI) was calculated. Forty-seven healthy adults were included (19.9 ± 1.75 years). The inclusion of both types of diets did not modify the components of the DQI, such as the diversity, equilibrium, adequacy and excess. However, when only the first period was analyzed, a significant decrease in the consumption of fruits and vegetables was observed in those participants who received the PB diet (intervention group). The CC diet (control group) significantly reduced the consumption of fish and eggs, total DQI, and DQI quality component. The expected effect was observed in the significant increment of consumption of red meat after the intervention period.