Hair growth facts

A human scalp has about 100,000 hair follicles.
Each strand of hair grows for 3-5 years before shedding and re-growing.
Shedding 50-100 strands of hair per day is normal.
People with long hair shed more, because their hairs are longer when they shed. The hair they shed is the hair that a haircut would have removed.
Cutting hair does not make it grow faster or slower.
Maximum hair length is determined by how fast your hair grows and how long it stays in the growth phase, which is determined by your DNA.
Hair is always thickest near the head because there are always some strands in an early part of their growth phase.
The growth rate of hair in men and women does not significantly differ.
Hair grows from the scalp outward, unlike trees. Trees grow from the tips of branches.

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