Lack of blood supply

Some doctors assert that a lack of blood supply contributes to hair
loss. Bald skin gradually loses some of its blood supply and as a
result becomes thin and shiny. These changes, however, come only
after the loss of hair and is not the cause of the hair loss.
Hair follicles are some of the most rapidly metabolizing cells in the
body. Growing hair requires the proper oxygen and nutrition that
comes with a good blood supply in a healthy body. When hair folli-
cles are transplanted into skin grafts or scar tissue, both of which
may have a relatively poor blood supply, the presence of the
grafted hair causes the local blood supply to increase. The end
result is that as the hair grows, so does the blood supply.