Gradually restores lost color to gray hair. Natural-looking color: Day by day, GRECIAN gradually replaces gray with natural-looking color. You can stop anytime and leave a little gray, or keep going until all the gray is gone. And it looks so natural no one can tell you colored your hair - they'll just know you look great. Different hair colors are the result of different amounts of melanin, nature's coloring protein. Darker hair simply has more melanin than lighter hair. As melanin production decreases with age, hair turns gray. The product has a unique ability to replace lost melanin with a similar-acting pigment. You can regain just the right amount of lost color by applying GRECIAN for fewer or more days. Contains a hair-thickening ingredient that works by expanding the hair's diameter. Plus, it actually repairs and strengthens hair, reducing hair loss from breakage. The result: healthier, thicker-looking hair.