Online searches for ‘how to clean your makeup brushes’ spiked by a staggering 4350 per cent recently, according to beauty discovery website Cosmetify.

This follows from its research which found one quarter (26 per cent) of British women have never cleaned their makeup brushes, ever. And for those women who do wash their brushes, 37 per cent do so every six months. That’s quite a lot of time for foundation, powder and dirt to build up on those (what we imagine were once soft) bristles. So, how bad is it really to leave you makeup brushes unwashed?

We’ve spoken to skincare expert, Dr Emma Wedgeworth and make-up artist, Lisa Potter-Dixon to answer all of our questions and trust us – they’ll convince you to start cleaning those tools immediately, if not sooner.

Firstly, why do we need to clean our makeup brushes?

“With each use, a make-up brush builds up a collection of product residue, skin cells and excess oil,” explains Wedgeworth, “this combination is not only pore blocking, but can act as an ideal breeding ground for microorganisms like bacteria and fungi.”

Using unwashed brushes, therefore, can actually make us more susceptible to skin infections – particularly if there are any areas of broken skin. “If you are acne prone you definitely don’t want to be using a dirty brush as the unsavoury combination of old make-up mixed with oil and dead skin cells is highly pore blocking,” explains Wedgeworth.

Potter-Dixon agrees. “I get a lot of clients asking me why they suddenly have irritated skin,” says Potter-Dixon, “My answer? ‘When was the last time you cleaned your makeup brushes?’

So, how often should we be cleaning our makeup brushes?

According to Wedgeworth, “it’s a good idea to get into the habit of cleaning them every 7-10 days.” Slightly more than 6 months, then…

As a professional make-up artist, Potter-Dixon cleans them after every use when using them on other people. “For personal use, I try and clean them once a week. If that’s not feasible, even once a month is better than nothing.”

Is it bad to share your makeup brushes with others?

Cosmetify found from its research poll that more than two thirds of respondents have previously shared their make-up brushes with another person. And, I mean, why not? It saves precious handbag space on a night out if only one of you need to take a bronzing brush. It’s also fun to swap and share with friends.

But, unfortunately, it’s not so fun for our skin. “We all have a unique balance of bacteria and fungi on our skin and we get into a natural groove with these microorganisms. Using someone else’s brush will expose us to a whole host of different bacteria which our skin’s immune system is not used to and can put us more at risk of infection,” says Wedgeworth.

What are the best cleaning products for our beauty tools?

Thankfully, there are a whole host of new, fool-proof cleaning tools that can be super quick to use. Some of them are probably in your bathroom already, too.

“Your shampoo is a good starting place as you know you are not sensitive to it and well, it’s great for cleaning hair,” advises Potter-Dixon. “Always double cleanse your brushes and leave to dry naturally on a towel. Heat drying them can melt the glue that holds the bristles in place.”

Potter-Dixon’s favourite cleaning products include “the beauty blender solid – this gives a real deep clean. I also love the Sigma brush cleaning glove, it’s amazing if you have a lot of brushes to clean as it has different compartments to deep clean different sized brushes. Cinema secrets solution is also brilliant, as is the real techniques cleanse.”

Her top trick? “Always remember to be gentle when washing your brushes and always mold the head back into shape whilst wet so that it dries that way.”

Time to have a spring clean…

The article originally appeared on GraziaDaily.co.uk.