A 2016 study found that all skin and eye products in salons used by multiple people were contaminated with bacteria. Nineteen percent of the makeup brushes were also found to contain fungus or yeast. So ultimately, what’s the lesson? First, it’s essential to know how to clean makeup brushes, how often to do so, and when to get rid of them altogether.

Every day, we use makeup brushes to paint, contour, and highlight our faces, but we may not always be able to say the same about how often we clean our most frequently used brushes. It’s not enough to give them a good wash about once a month. Keeping our tools clean can help prevent breakouts, say dermatologists and makeup artists. They say we should suds them up more often.