Seeds from Golden Rain acacias like these in Wales provide the active ingredient for a pill to help people stop smoking. Tom Patterson/Flickr hide caption

itoggle caption Tom Patterson/Flickr

An increase in toxic chemicals in cigarettes may also be to blame for the high risk of bladder cancer for women who smoke. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Early morning cigarettes are a proxy for the level of addiction, researchers say. iStockphoto.com hide caption

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The FDA recently updated the anti-smoking messages it includes on cigarette packages to add graphic images. Mario Tama/Getty Images hide caption

itoggle caption Mario Tama/Getty Images

Three examples of proposed warning graphics that will appear on cigarette packaging as part of the government's new tobacco prevention efforts. Evan Vucci/AP hide caption

itoggle caption Evan Vucci/AP