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Study: Early-morning smoking increases cancer risk

A person is shown smoking a cigarette in this undated file image.

August 8, 2011 12:00:00 AM PDT
Smoking cigarettes first thing in the morning may increase the risk of lung, head and neck cancers, according to a new study.

People who smoked within a half hour of waking up were 59 percent more at risk for head and neck cancers and 79 percent more at risk for lung cancer than smokers who waited at least an hour to smoke after waking up.

Scientists think smoking early in the day may be riskier because it shows a stronger nicotine addiction.

The study is online in the journal Cancer.