Does shaving affect hair growth?

Does Shaving Change How Hair Grows In?

Shaving does not change the structure, thickness, or growth rate of hair. This is supported by high-quality evidence from multiple guidelines and research studies 1.

Scientific Facts About Hair Growth and Shaving

Hair Growth Cycle and Rate

• Hair grows from follicles beneath the skin at a rate of approximately 1 cm per month 1
• Hair growth occurs in cycles with three phases: anagen (growth), catagen (transition), and telogen (resting)
• The growth rate varies by body location, gender, and ethnicity 2
• Terminal (scalp) hairs grow faster than body hairs in most locations 2

Effects of Shaving on Hair

• Shaving only cuts the hair shaft at the skin surface and does not affect:
  • The hair follicle structure
  • Hair growth rate
  • Hair thickness
  • Hair color
  • Hair texture

Common Misconceptions

• The perception that hair grows back thicker or darker after shaving is an illusion caused by:
  1. The blunt-cut edge of newly shaved hair (compared to the natural tapered end of unshaved hair)
  2. The lack of sun bleaching in newly emerged hair
  3. The contrast between short, dark stubble against light skin

Evidence from Guidelines and Research

The American Academy of Pediatrics notes that hair grows at a consistent rate of approximately 1 cm per month, regardless of whether it has been shaved 1. This guideline specifically mentions that hair structure, growth rate, and other characteristics are determined by genetics and hormonal factors, not by shaving.

The British Association of Dermatologists' guidelines for management of hair conditions do not indicate any changes to hair structure or growth patterns resulting from shaving 1. Their comprehensive review of hair growth mechanisms makes no mention of shaving altering hair characteristics.

In surgical settings, the Enhanced Recovery After Surgery Society notes that if hair removal is necessary for surgical visualization, clipping is preferred over shaving to reduce infection risk, but neither method affects the underlying hair growth patterns 1.

Special Considerations

Medical Hair Removal

• In medical contexts, when hair removal is necessary (such as before surgery), clipping is preferred over shaving to reduce surgical site infection risk 1
• For patients with congenital melanocytic nevi who desire hair removal, shaving is considered a low-risk option along with waxing, threading, chemical depilation, electrolysis, or trimming 1

Hair Removal for Cosmetic Procedures

• For laser hair removal procedures, a study showed no significant difference in effectiveness whether the area was pre-shaved or pre-waxed 3, further supporting that shaving does not fundamentally alter hair growth

Conclusion

The scientific evidence clearly demonstrates that shaving does not change how hair grows in terms of thickness, rate, color, or texture. The perception that it does is based on visual illusion rather than actual biological changes to the hair follicle or shaft.