Ah, blonde hair. It conjures up the nostalgia of Sun-In, the sexiness of Brigitte Bardot and makes us wish we all could be California girls. Except when brassy tones creep in and ruin the sun-lifted effect. There’s no need to lose your cool (pardon the pun), though, as that’s when the best purple shampoo swoops in with its impressive hue-restoring powers.
If you’re new to this kind of shampoo, you’re in luck – we’ve spoken to some of the industry’s biggest hair experts to explain exactly how it works and how to use it. Keep reading for everything you need to know…
What causes brassy hair?
It’s arguably blonde hair’s biggest nemesis: brassiness. Why does it happen? ‘Lighter strands often struggle to look shiny and healthy,’ says Steve Shiel, scientific director at L’Oréal. ‘This is because free radicals in the colouring process break down protein so blonde hair becomes porous.’
This porousness means bleached hair soaks up unwanted minerals and metals in your tap water and acquires a yellow tinge over time. ‘It also means that blonde hair absorbs light instead of reflecting it and is more prone to damage,’ adds Shiel.
What is purple shampoo?
Put simply, violet-hued shampoo is the haircare equivalent of a surly bodyguard. It protects against dullness and unwanted warm tones between colour appointments.
‘Purple shampoo neutralises the yellow in blonde hair, leaving a creamy to ash result,’ explains leading colourist and celebrity favourite, Josh Wood. ‘This is because yellow and purple sit opposite each other on the colour wheel.’
So when you wash with this particular shade of shampoo, it deposits purple pigment into blonde hair, to counteract any yellowy tones that start to shine through.
How to use purple shampoo
This may seem obvious, but a violet-based shampoo is not made for your daily lather.
Those who bleach their hair and live in hard water areas (which creates more mineral build-up on strands), should only use it once a week. Meaning, one bottle will last you until your next colour appointment, if not longer.
But Zoe Irwin, creative director at John Frieda Salons, advises clients to be careful as purple-based products can be drying.
‘I decant half my purple shampoo into half a bottle of Oribe Shampoo For Moisture Control (£45 | Cult Beauty),’ she says.
‘The effect is softer, both in terms of the colour and how my hair feels afterwards. I wouldn’t recommend taking your purple shampoo right down to the ends. The hair there can be up to four years old so will grab onto too much of the purple pigment.
‘If you can’t avoid it, coat the ends in conditioner first to create a hydrating base and to dilute the shampoo. Then apply your purple shampoo in an ‘s’ shape on mid-lengths and work it in with your fingers to deposit the pigment evenly.’
For how long should you leave purple shampoo in?
It all depends on the instructions on the specific bottle, but not overdoing it is key. ‘If you leave a purple shampoo on for too long, your hair will have a blue-purple tinge to it,’ Irwin cautions.
Session stylist Ali Pirzadeh concurs and recommends using your regular conditioner afterwards. ‘I wouldn’t bother with a purple conditioner as well, as you want to make sure your hair is still being nourished.’
What’s the difference between toner and purple shampoo?
Toners cool down or warm up your colour in between salon appointments.
An at-home version is the equivalent of a semi-permanent colour treatment mask. Free from peroxide or ammonia, it won’t actually lift your colour, but it penetrates the hair cuticle and deposits a small amount of lilac colour. This brightens old hair dye and boosts its undertones as well as preventing fade and ramping up the shine.
L’Oréal Paris Elvive Colour Protect Purple Reviving Oil, £12.99 | Feelunique
This is the first-ever brass-banishing oil. Designed to be used in-between hair washes, it should be used on clean towel-dried hair. Work 2/3 drops into dry and brittle ends for instant toning, as well as hydration.
Below are our picks for the best purple shampoo for blonde hair. Our Senior Beauty Editor, Katie Thomas, has handpicked these after testing each one personally. She has blonde hair and loves it to have an ashy tone. Any that she wasn’t keen on, just didn’t make the list. The things that she particularly focused on were: how her hair felt afterwards – did it feel dry at all or soft to the touch, and how well it took down brassiness.
Here are her recommendations for the best purple shampoos…