Haircutting without Pain

Painless haircutting
Photo: Alexander’s Images/Canva
Q: Question: Why doesn't it hurt when you get your hair cut? Why is a haircut painless?
A: When hair is cut, the absence of pain has to do with the anatomy of the hair itself. The unique anatomy of hair allows it to be cut and styled without experiencing discomfort and pain.
Cutting hair doesn't cause pain because hair itself doesn't have nerves or blood vessels. In contrast to living tissues like the skin, organs, or muscles, hair is composed of dead cells. The hair shaft, the visible part of the hair, is made up of a protein called keratin. Keratin is a strong protein that forms the structure of hair, nails, and the outer layer of the skin.
Nerves are responsible for transmitting signals of pain, and since hair lacks nerves, it cannot register or transmit the sensation of pain. The hair follicle, the structure beneath the skin from which a hair grows, does contain nerve endings, but these are located in the surrounding skin rather than in the hair itself. When you cut your hair, you are essentially trimming the dead, keratinized cells that are devoid of sensation.
Anatomy of hair
Image: Science Photo Library/Canva
When you cut your hair, you're changing its length and shape without affecting the underlying living structures. Haircutting is essentially a process of cutting dead protein strands. The scissors interact with the non-living part of the hair, and there are no nerve endings present to transmit pain signals. The cutting process is more akin to altering a non-living material than affecting a living organism.
In contrast, cutting into living tissues, such as the skin or underlying flesh, would elicit a pain response because these areas are rich in nerves and blood vessels. So, the absence of pain when cutting hair is due to the fact that hair, at least its visible part, is a non-living part of our body.
See also:
How fast does hair grow?
What is hair made of and how does it grow?