Lifetime Cigarette Smoking and Colorectal Cancer Incidence in the Physicians' Health Study I

5 (0.9) 1.5 (0.9) 1.4 (0.9) Mean fruit servings (SD), No. per day 0.9 (0.7) 0.8 (0.7) 0.8 (0.7) Smoking history, pack-years‡