Recently, I found out that I’ve been applying my dry shampoo wrong for years (folks, we’re not meant to spray it directly onto the scalp).
Just when I wrapped my incorrectly-sprayed head around that fact, though, another blow comes: I’ve not even been leaving dry shampoo in my hair the right way, apparently.
Not only do experts advise leaving the oil-absorbing product on your hair for at least two minutes and as long as 10, but it turns out dermatologists don’t think we should just let the product sit there after spraying.
What?!
According to the American Academy of Dermatology Association (AAD), we’re meant to brush away the dry shampoo after it has done its job.
That’s because, AAD explains, the product absorbs oil (a bit like kitchen roll does for spills).
Once it’s done that, which may take a couple of minutes, there’s no real reason to keep the grease-containing powder in your hair.
Instead, they say, “when you brush or comb out dry shampoo, it removes the oil”.
Still, if (like me) you’re now feeling grossed out by all the dry shampoo you’ve let linger on your roots for hours at a time, we probably don’t need to be too worried.
Board-certified dermatologist Dr Zoe Draelos told the publication: “Nothing bad will happen if you leave dry shampoo on for longer than directed. You just won’t get the best results.”
Well, that’s my morning routine altered forever.
How many days in a row should you use dry shampoo?
We’ve written before at HuffPost UK about how important it is to wash your hair whenever it looks and feels like it needs it ― “oil training,” or letting your hair get greasy so it “learns” not to absorb your scalp’s sebum, has largely been debunked.
It’s important to remember that despite the name, dry shampoo doesn’t clean your scalp. It simply blots it.
So, it’s not surprising that dermatologist Dr Lindsey Zubritsky told Byrdie that while those with oilier hair will be able to safely use more dry shampoo than someone with a drier scalp, she recommends dry shampoo shouldn’t be used for more than two days in a row.
She added: “The risk of overusing dry shampoo is that it can build up in your scalp, resulting in occlusion of your hair follicles. Over time, this can lead to inflammation, acne, or dandruff, resulting in an unhealthy scalp environment.”