Here's why:
* Hair thickness is determined by genetics: The size and density of your hair follicles are determined by your genes. Cutting your hair doesn't change your genetic makeup or the structure of your follicles.
* Hair can appear thicker after a cut: There are a few reasons why hair might *seem* thicker after a trim:
* Blunt ends: Cutting off split ends and creating a blunt end at the bottom of the hair strand can make it appear fuller and less wispy.
* Removal of damage: Damaged hair tends to be thinner and more brittle. Removing this damage can create the illusion of thicker hair.
* Shorter hair is bouncier: Shorter hair typically has more volume and lift, which can make it appear fuller.
* Growing out new hair: Cutting off hair stimulates the follicle to produce new hair. The shorter the hair, the less there is to weigh it down.
In short, cutting your hair can improve its appearance and give the *illusion* of thickness, but it doesn't actually change the thickness of individual hair strands or increase the number of hairs on your head.