What property of hair does the melanin content directly influence?

The melanin content in hair plays a critical role in determining its color. Melanin is a natural pigment produced by melanocytes in the hair follicles, and it comes in two primary types: eumelanin (which can be black or brown) and pheomelanin (which is yellow or red). The specific ratio and concentration of these types of melanin dictate the overall color of an individual's hair, whether it appears blonde, brunette, red, or black.

In contrast, length, strength, and elasticity are properties influenced by other factors such as genetics, health, hair care practices, and the hair's structural integrity. While melanin impacts the visual appearance of the hair, it does not contribute directly to its physical properties like length or the ability to stretch without breaking. Understanding this relationship between melanin and hair color is crucial for any haircolorist as it guides them in formulating hair dye and customizing services for clients based on their natural pigmentation.