Gray Hair Caused by Stress (Cell Stress, That Is)
Christine Dell'Amore
National Geographic News
June 16, 2009
(link to full article below)
Work or personal stress may make you want to pull your hair out, but it's cellular stress that actually turns it gray, a new study has found.
That's because DNA is "under constant attack" by damaging agents, such as chemicals, ultraviolet light, and ionizing radiation, according to study lead author Emi Nishimura of Tokyo Medical and Dental University.
A single mammal cell can encounter up to 100,000 events a day that damage DNA, Nishimura added in a statement.
The stem cells within hair follicles responsible for color are the most impacted by this irreparable DNA weathering.
Stem cells are cells in the body that can reproduce indefinitely and that have the potential to "mature" into other, more specialized cells. The stem cells in hair follicles mature into melanocytes, or cells that produce the pigment melanin.
(Related: "Human Skin Cells Given Stem Cell Properties.")
In younger people, the hair's stem cells maintain a balance between those that reproduce and those that turn into pigment cells, so that pigment is constantly being added to growing hair.
To read the full article:
http://news.nationalgeographic.com/news/2009/06/090616-stress-gray-hair.html?source=email_gg_20090624
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment