Is 30 Days Without Washing the Secret to Healthy Hair?

Could going 30 days without shampooing be the secret to healthy hair? Some TikTok users who practice “hair training” say that it is.

To clarify, the act of “hair training” isn’t actually anything new—it just doesn’t usually require a full month between washes. It’s often experts’ first of piece of advice when it comes to preventing and treating greasy hair, and the method requires ”training” your hair and scalp to produce less oil by slowly extending the period between shampoos over time. Typically, the traditional type of hair training recommends not washing your hair for a few days to a week. Sounds pretty normal and doable, right?

Right! Except that’s not how the viral TikTok is going about it. The top videos for “hair training” as both a hashtag and phrase—which have already amassed a combined 411 million views—feature users who claim their “long hair” is the direct result of washing their hair once a month. Some say they have gone as long as 33 days without shampooing.

Is their hair pretty? Yes, very much so. But does that mean such severe forms of hair training are good for everyone’s hair? Definitely not. In fact, depending on your hair type and scalp health, it could even result in dandruff, folliculitis, odor, and skin infections that could result in hair loss, according to double board-certified dermatologist Brendan Camp, MD, clinical assistant professor of dermatology at Weill Cornell Medical College.

“Less washing and altered scalp hygiene may also predispose the skin to infections with bacteria or fungi,” Dr. Camp explains. “If certain scalp conditions are left untreated, such as psoriasis and seborrheic dermatitis, it is possible that associated inflammation could damage hair and impact hair growth.”

Washing your hair infrequently does not directly cause hair loss, of course.

“But if the scalp becomes excessively oily or develops conditions like dandruff due to infrequent washing, it can indirectly contribute to hair loss,” adds celebrity hairstylist and L’Oréal Professionnel global ambassador Min Kim.

So do the experts recommend this method? “I don’t recommend waiting a full month to wash your hair,” Dr. Camp says. “Though you may not be able to see it well, scalp skin produces oil, accumulates dead skin cells, and is prone to acne and irritation, just like the skin on your face and body. Waiting too long between washes causes buildup of scale, oil, sweat, and hair product, which can contribute to dandruff, folliculitis, odor, and acne.”