“Shaving makes hair grow back thicker and darker.”

Many people observe that after shaving, their hair seems to return thicker and darker, leading to the common misconception that the act of shaving somehow alters hair growth. This belief has likely persisted for as long as razors have existed, with personal experience seeming to confirm the visual and tactile changes. For instance, the natural progression of hair growth during puberty, when hair often becomes coarser and darker, can coincide with a person's first experiences with shaving, creating a false association. Some historical practices, such as shaving a baby's head to encourage stronger hair, also reflect this enduring, albeit incorrect, idea.

However, scientific evidence consistently debunks this myth. Hair grows from follicles located beneath the skin's surface, and these follicles are the true determinants of hair's color, thickness, and overall structure. Shaving merely removes the visible part of the hair, the shaft, at the skin's surface; it has no impact on the living follicle underneath. Numerous clinical studies have confirmed that shaving does not affect the hair follicle's structure or growth pattern, nor does it change the actual thickness or color of the hair that regrows. Hair growth is primarily controlled by genetics and hormones, not by external actions like cutting.

The illusion of thicker, darker hair after shaving stems from several factors. When a razor cuts hair, it creates a blunt tip, unlike the naturally tapered end of an unshaven hair. As this blunted hair begins to grow back, it feels coarser and can appear more noticeable and denser to the touch and eye. Additionally, newly regrown hair hasn't been exposed to environmental elements like sunlight, soaps, or other chemicals, which can subtly lighten hair over time. This unexposed, blunt-tipped hair therefore appears darker and more prominent, reinforcing the mistaken belief that shaving has somehow changed its fundamental characteristics.