What effect does the scalp's natural oil have on hair color?

The scalp's natural oil plays a significant role in the hair coloring process, as it can create a barrier that affects the absorption of the hair color. When the hair is overly oily, the color molecules struggle to penetrate effectively into the hair shaft. This barrier diminishes the overall efficacy of the color application, possibly leading to uneven results or less vibrant color.

Understanding this concept is crucial for achieving the best possible results when coloring hair. Proper preparation, including shampooing to reduce excess oil, can ensure that the hair is in the optimal condition for color absorption. This highlights the importance of considering the scalp's natural oil levels as part of the overall coloring process to ensure an even and vibrant finish.