Sometimes, gray hair can look dull and brassy. That’s because our hair doesn’t lose all of its pigment at once—it happens gradually and yellow is the last color to go, explains Jay Small, celebrity hairstylist and founder of gray hair-care line Arey. Luckily, using purple shampoo on gray hair is the perfect fix.

“Those who experience gray hair may notice a warmth or brassiness, which is when I would recommend using purple shampoo,” says Small. “The purple shampoo will add the missing primary colors, red and blue, to the yellow in the hair strand. When your hair strand has equal amounts of these primary colors it will appear or reflect neutral and balanced.”

Plus, gray hair can sometimes turn yellow when it gets stained, explains Tom Smith, celebrity hairstylist and international color creative director for evo hair.

“Gray hair, more accurately described as hair without pigment, has a tendency to pick up stains from styling products, pollution, or hard water,” says Smith. “This often shows up as yellow golden stains on naturally grey hair.”

Note that while the yellow is masked by the shampoo, it’s not removed. So you’ll need to use purple shampoo regularly to maintain results.

“Depending upon how white you want your grey hair to appear would determine the frequency of use,” says Small. “For natural-looking gray hair I would use purple shampoo once a week, and for more extreme, icier grey looks, I would use purple shampoo every other wash.”

Plus, since pigment is what allows hair to hold on to moisture and nutrients, using purple shampoo can also make your strands look more lively.

“Purple shampoo deposits color molecules into your hair strand—for gray hair, this addition of color molecules can make hair look and feel smoother,” says Small. “If your hair looks too warm or feels a little limp try giving it a purple shampoo boost”

Expert-favorite purple shampoos for gray hair

Joico Color Balance Purple Shampoo — $23.00 to $43.00

For the most pigment per shampoo, Small recommends this shampoo from Joico. It strengthens and protects hair while cleansing and depositing color.

evo Fabuloso Platinum Shampoo — $34.00

My favorite is evo fabuloso platinum shampoo which was formulated to have the highest violet pigment load but still effectively clean the hair,” says Smith. “It delivers much-needed nutrients and nourishment to leave the hair feeling soft and healthy, unlike many other purple shampoos which can tend to feel a little too harsh on the condition of the hair.”

Olaplex No.4P Blonde Enhancer Toning Shampoo — $30.00

For those who don’t have super brassy hair and need less pigment, Small likes this Olaplex shampoo. It uses gentle ingredients to brighten your strands while rebuilding broken and weakened bonds.

Oribe Bright Blonde Shampoo — $17.00 to $46.00

If you’re looking to really treat your strands, grab this Oribe shampoo. “It’s expensive but you are worth it,” says Small. It will leave your stands looking luminous.

Don’t use purple shampoo for every wash

“Purple shampoo is a tool in your hair-care routine that I would use when needed, but not every day,” says Small. “Purple shampoos are designed to deposit pigment and not over cleanse, so it’s important to use a gentle shampoo and conditioner in-between your purple shampoo applications.”

Arey Wash Sampoo — $48.00

When you’re not using purple shampoo, Small recommends this one from his line Arey. It gently cleanses and includes a peptide that reduces signs of aging hair by stimulating cell production and leading to stronger, healthier strands.

For more editor-approved hair-care tips, check out the video below.

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