The so-called "no-poo" trend — washing hair without shampoo — is spreading rapidly among Generation Z on social media platforms. Interest has grown after overseas celebrities including Gwyneth Paltrow, Johnny Depp and Adele revealed they avoid shampoo to prevent hair loss. However, experts warn the practice lacks scientific backing and could actually accelerate hair loss and premature graying.
The no-poo movement originated from claims that surfactants and chemical ingredients in shampoo damage the scalp and cause hair loss. Proponents argue that daily shampooing strips away even the minimal sebum needed to protect the scalp, drying it out and triggering the body to produce even more oil to compensate.
The problem arises when sebum is not washed away in time. Sebum is a natural substance that protects hair and the scalp, but when it accumulates excessively around hair follicles, it traps dihydrotestosterone (DHT), a hormone that causes hair loss. DHT is the primary agent that shrinks follicles and makes hair thinner and shorter. Prolonged avoidance of shampoo leads not only to sebum buildup but also to bacterial and fungal overgrowth, inflammatory reactions and oxidative stress — all of which compound to deteriorate follicle health.
A common belief holds that frequent hair washing worsens hair loss, but experts say this is a misconception. Even in the early stages of androgenetic alopecia (AGA), chronic inflammation around follicles has been found to disrupt the hair growth cycle, and failing to properly cleanse the scalp is more likely to worsen hair loss. Even people without hair loss can develop premature gray hair if they neglect scalp hygiene.
The level of risk also varies by scalp type. For those with oily scalps or seborrheic dermatitis, washing with water alone without shampoo can cause further sebum buildup and worsen inflammation, making the no-poo approach particularly dangerous. Another no-poo method involves rinsing the scalp with baking soda diluted in water, but its alkaline nature clashes with the scalp's acidic environment and weakens hair protein structure over time.
Experts advise that rather than quitting shampoo entirely, adjusting the amount and frequency to suit one's scalp type is the more practical approach. Gradually reducing shampoo use while thoroughly cleansing the scalp at least once every three days can benefit scalp health. It is also worth noting that the cause of hair loss more often lies in improper cleansing habits, dryness and styling practices rather than shampoo itself.