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Gray hair can be a concern for many, especially when it appears early. Coffee, a daily beverage, may help temporarily darken gray strands due to its natural pigments. However, there is no scientific evidence that adding coffee to shampoo can prevent graying or restore lost pigment. While applying strong, cooled coffee to clean, damp hair may provide a subtle dark tint, the effect varies and fades with washing. It's important to test for reactions before use. Daily coffee consumption has not been proven to prevent graying or restore natural hair color. For a more reliable solution, specially formulated hair dyes are recommended.