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.

The stem cells within hair follicles responsible for color are the most impacted by this irreparable DNA weathering.

[Read](http://news.nationalgeographic.com/news/2009/06/090616-stress-gray-hair.html “Read the Article”) (National Geographic)