Things we ponder when we're trying to fall asleep at night: the fate of the Starks in Game of Thrones, if vagina facials are a good idea, and the age-old question, "Is it bad to wash your hair every day?" People seem firmly divided on this issue. Some would never, ever go more than a day without washing their hair, and others can't imagine washing their hair more than once a week. So who's right? (Not that this is about taking sides, but like, we're on Team Wash Hair as Little as Possible.)
We spoke to Dominic Burg, chief scientist at Évolis Professional and a hair biologist, microbiologist, trichologist (basically, he knows what he's talking about) to get his take on this debate.
Meet the Expert
Dominic Burg is the chief scientist at Évolis Professional and director of operations at Cellmid Limited. Burg focuses on biotechnological advances in the world of hair and scalp health.
How Shampoo Works
Shampoo contains surfactants which come together with your skin's sebum (a substance that coats and protects follicles), and this allows it to mix with water in order to cleanse the hair of any dirt and grease.
Is It Bad to Wash Your Hair Every Day?
Here's the sitch: Your skin is covered in billions of good bacteria from about 1000 species, says Burg. These bacteria are helpful, and the collection of them is called your microbiome. "The population of microbes help maintain the skin pH and actually prevent bad microbes from colonizing the skin by competing for nutrients and also producing molecules that bad bacteria don’t like," he explains.
Okay, so what does this have to do with hair? "Too frequent washing of the scalp with harsh cleansers can upset that microbiome, and an imbalance in the microbiome can lead to scalp problems," Burg says. Basically, washing your hair too much can throw off your scalp's microbiome, which can let bad bacteria and fungi take over and cause things like inflammation, according to Burg.
He recommends gently cleansing your scalp two to three times per week to help remove excess sebum.
Could You Be Using the Wrong Products?
Here's the other part: Burg says if you feel like you need to wash your hair every day because it's dirty and/or greasy, you're probably using the wrong shampoo for your hair type. "Everyone's skin and follicles will produce different levels of oils, which is normal and actually good for hair. The main challenge is finding the right balance with the right products for you to maintain your style without disrupting your natural microbiome, pH, and natural oils," he explains.
He cautions against using shampoos with sulfates or silicones because they can be too drying or too heavy, respectively.
"Look for a gentle, sulfate-free cleanser that is balanced with essential oils so it won't strip out your hair's natural oils, and make sure you use silicone-free conditioners with natural essential oils and conditioning agents to ensure cuticle health," he recommends.
The Final Takeaway
If your hair seems brittle and lifeless, you could be a victim of hair over-washing. Burg's prescription is using a hydrating, nourishing mask (and don't shampoo as frequently).
Saxena R, Mittal P, Clavaud C, et al. Comparison of healthy and dandruff scalp microbiome reveals the role of commensals in scalp health. Front Cell Infect Microbiol. 2018;8:346. doi:10.3389/fcimb.2018.00346
Gavazzoni Dias MFR. Pro and contra of cleansing conditioners. Skin Appendage Disord. 2019;5(3):131-134. doi:10.1159/000493588
Cleveland Clinic. The dirty truth about washing your hair. Updated August 14, 2018.