How often should you wash curly hair?

Almost every other page about curly hair says wash less. The dermatology literature says the opposite, and the reason is worth following because it explains why the common advice feels right and still causes problems.

Why washing less feels correct

Curly and coily hair grows from curved follicles, producing a coiled fibre. That geometry is thought to “impair the distribution and absorption of sebum along the hair shaft”, so the length is drier than on straight hair no matter what you do, and the bends are stress points where the fibre breaks.

Wash it and it feels drier. Skip washes and it feels better. The immediate feedback is real and it points one way.

What the longer view shows

The review names the practice and its consequence directly. The belief “that frequent shampoo use leads to dryness and breakage has fostered a cultural adoption of bi-monthly and monthly hair washing, along with prolonged protective styling methods in adults. This practice increases the risk of developing seborrheic dermatitis and in some cases, traction alopecia (TA).”

Two conditions, both worse than dryness. Seborrheic dermatitis is a scalp condition that then requires medicated shampoo, which is harsher than what you were avoiding. Traction alopecia is hair loss from sustained pull, and it comes from the prolonged protective styling that goes with stretched wash schedules.

Against that: “recent studies suggest that weekly washing of Afro-textured hair with appropriate products regulates the scalp microenvironment and reduces product buildup, both which counter hair breakage”.

Weekly, with appropriate products. The qualifier is doing work: this is not an argument for a harsh shampoo every week.

What appropriate means in practice

Match the cleanser to what you are actually applying. If your conditioners contain water-insoluble silicones, something has to remove them; if they do not, a gentle cleanser is enough. That trade is set out in the question on sulfates.

Condition after every wash. The washing is not the damaging part; washing without restoring slip is.

Watch the styling as much as the shampoo. Tension at the hairline over months is what causes traction alopecia, and no product prevents it.

If the scalp is already flaking

Medicated shampoos have monograph strengths behind them, and two pieces of guidance make them far easier to live with.

Apply to the scalp, not the lengths: “the shampoo should be applied directly to the scalp rather than the hair shafts to minimize dryness”. And do not let it sit, because “prolonged contact time is not needed for medicated shampoos to be effective”.

Most of the reason people find Pyrithione zinc and tar shampoos unbearably drying is delivery rather than the active.

The short answer

Weekly is the figure the evidence supports for most people, with the products matched to the routine and conditioning afterwards. Stretching to monthly trades a manageable problem for two harder ones, which is the argument made in full on the curly and coily hair page.