You're probably aware that starting the day by rolling out of bed and having a cigarette isn't good for you, but Penn State researchers say it may be even worse than you think. A study of 7,610 smokers found that smoking in the first 30 minutes after waking nearly doubles the risk of developing lung cancer. Another study found those who start smoking immediately are 59% more likely to develop a tumor, compared to those who wait an hour.

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