Remember that old ad about washing the gray right out of your hair? You can wash the color right out of it too if you overdo it. I once found this out the hard way when my richly espresso-hued locks turned to weak tea in two weeks. Even permanent hair color is no match for over-washing, and that goes for salon color as well as the shades from at-home coloring kits.
The most important wash is the first one after coloring your hair. Stylists and package inserts recommend a wait of 24 to 48 hours before using shampoo on freshly dyed hair, but the closer you get to the 48-hour mark, the better. If you like the reds as much as I do, count on a two-day waiting period or risk washing your color–and your money–down the drain.
So after that initial shampoo, how much washing is too much? It depends on these four factors:
Your Shampoo and Conditioner
To preserve your color, look for hair-care products designed for use on color-treated hair. There’s a word on most shampoo bottles that you absolutely want to ignore: “Repeat.” One wash–even with gentle color-safe formulas–should be plenty unless you’ve been exploring abandoned coal mines. Stick to every other day or every third day depending on your shade and how much of a change you’ve made.
If you love your color, avoid clarifying shampoos and hot-oil treatments at all costs. Both will quickly leach added color from the hair shaft. In fact, they’re so good at doing this that my stylist recommends them to clients who’ve chosen a too-dark shade of at-home color and want to get rid of it.
Your New Hair Color
Some pigments naturally last longer than others. Shades of red are notoriously fugitive and can begin to change noticeably after only a couple of weeks of washing. Dark colors are also prone to lightening with over-washing. If you choose a vivid red or a rich dark shade, can you get away with every three days? Not everyone can; if you exercise vigorously, work in a hot environment, or tend toward scalp oiliness, aim for every other day. Otherwise, the longer you go between washes, the better your red will be.
Blondes won’t lose their color as quickly or noticeably as brunettes or redheads, but even they should stick to every other day. While they won’t lose as much pigment, blondes do risk drying their tresses unnecessarily from over-shampooing.
The Degree of Your Color Change
If you just went a few shades lighter, darker, or warmer, you can wash every other day with reasonable confidence. If your change is drastic–a natural blonde who’s gone raven-black, for example, or a brunette who’s gone platinum via double-processing–every third day is your maximum frequency if you want to keep your color true. Hair that’s undergone so dramatic a change is as delicate as old lace and needs to be handled with care.
The Texture of Your Hair
The more porous your hair, the more color it takes–and the more color it loses to overly vigorous washing. Think of a kitchen colander with very fine holes versus one with big holes; if you dunk it in water, the colander with fine holes takes some time both to fill and to empty while the one with large holes readily does both. If you have coarse hair, wash as infrequently as you can manage; your hair and your color will thank you for it.
How often you wash your color-treated hair depends on a combination of those four factors. Someone using color-safe shampoo on fine blonde hair that’s just a few shades from her natural color will see good results from every-other-day washing and could probably get away with a wash every day (although that wouldn’t be ideal). A brunette-turned-redhead with coarse hair should avoid washing her hair more frequently than once every third day–and if she can wear a hat and get away with four days between washes, even better.
The term “permanent” hair color is strictly relative, as anyone familiar with color-treated hair knows. With the right care, though, color can stay true for longer.