Cervical cancer screening systems aim to detect established HPV infections early. However, if there are no high-grade lesions, the intervention choice is basically limited to observational follow-up with recommendations on life habits like diet, to favor infection control. Therefore, it is important to establish specific feeding guidelines that provide clear evidence about the benefit they may bring against HPV infections. The present study evaluates the benefits of nutritional supplementation with a casein hydrolysate-based formula in patients with HR-HPV infection, compared with a non-supplemented control group. A total of 118 patients completed 6 months of follow-up. Significant differences between supplemented and control groups were observed for total or partial HR-HPV clearance at 6 months (74.6% vs 35.6%). Supplemented patients also suffered a lower occurrence of new intracervical lesions (0% vs 28.6%), a significantly greater resolution (67.4% vs 41.9%) and less progression of pre-existing lesions (4.7% vs 9.7%) at 6 months. An increase in the effectors of cellular immunity that could be responsible for their effect was also observed in supplemented patients. We conclude that nutritional supplementation with this casein hydrolysate-based formula could improve the outcomes of observational management of HPV infection.