Chronic hyperglycemia in diabetic patients can affect all body tissues, including peripheral tissues such as nails and hair. Nails are vital protective structures for the feet and hands, particularly in diabetic individuals who often experience impaired wound healing. Therefore, maintaining healthy nails is crucial for protecting these parts of the body. It is well-documented that the nails of diabetic patients undergo physicochemical changes due to the glycation of keratin. In this context, the objective of the present study is to utilize photobiomodulation (PBM) therapy to restore the biochemical integrity of healthy nails, thereby enhancing protection for diabetic patients. For this study, 30 healthy participants and 30 participants with type II diabetes (DM2) underwent PBM therapy twice a week, totaling 10 sessions. The point contact technique was used at two points located in the medial and lateral regions of the base of the nail on the fifth finger of the left hand. PBM was performed using low-intensity laser equipment, class B, with a Gallium-Aluminum Arsenide Diode (GaAlAs) semiconductor (808 nm; 100 mW; 4 J; 40 sec.; continuous). Nail fragments from the distal region were collected before (T0) and after (T2) therapeutic treatment. Biochemical changes attributed to PBM were measured using Confocal Raman Spectroscopy, with a Horiba confocal Raman spectrometer, model Xplorer, coupled to a laser with a wavelength of 785 nm and a power of approximately 15 mW. Spectral changes related to the biochemical components of the nail, such as keratin, disulfide bonds, and tyrosine, were evident after PBM. Additionally, changes were observed in the peak areas of 1654 cm-1 (α-helix) and 1622 cm-1 (β-sheet), which are protein markers for the groups investigated.