Mayonnaise contains beneficial ingredients like eggs, vinegar, lemon juice, and oils, which can improve hair moisture and reduce breakage. However, it does not directly promote hair growth. While it acts as an effective deep conditioner, its role in stimulating hair follicles is not scientifically proven.Mayonnaise contains beneficial ingredients like eggs, vinegar, lemon juice, and oils, which can improve hair moisture and reduce breakage. However, it does not directly promote hair growth. While it acts as an effective deep conditioner, its role in stimulating hair follicles is not scientifically proven.