Osmolytes, cellular compounds that maintain osmotic balance and integrity, are gaining attention in cosmetics for their ability to modulate protein folding and stability. Their incorporation into hair and skin care products enhances hydration and strengthens cellular structures. As the cosmetic industry seeks innovative and effective ingredients, osmolytes remain promising candidates for further advancing technologies. This study evaluates the protective effects of four osmolytes-betaine, erythritol, glycine, and isopentyldiol-on bovine serum albumin (BSA), as a substrate, under stressors such as UV irradiation, extreme temperatures, pH changes, surfactants, and oxidative stress. Protein stability was assessed via fluorescence emission. Only betaine at 0.50%