[영문]ObjectivesTo promote prevention strategies aimed at reducing the incidence of cancer or cardiovascular disease (CVD), we present a method to project the probability that a subject with given lifestyle risk factors will survive free from either of cancer or CVD.MethodsProjection models were developed from data from a cohort study conducted in Japan. During 1990?2003, 96,592 subjects were followed and 5797 cancer and 2591 CVD cases and 2395 deaths were identified. Smoking, alcohol intake and body mass index (BMI) were used as common risk factors in projection models.ResultsAccording to the projection of individualized probability, avoidance of smoking, excess alcohol intake and high BMI increased 10-year disease-free survival probability from 81.4% to 92.9% and from 88.0% to 94.3% in 50- to 54-year-old men and women, respectively. In terms of population average risk, smoking cessation and avoidance of excess alcohol exerted a large impact, while decreasing BMI had a small impact due to the small at-risk population.ConclusionsCurrent smoking, excess alcohol intake and obesity were suggested as common risk factors for cancer and CVD. Considering the distribution of risk factors in the Japanese population, smoking prevention/cessation and reduction of excess alcohol intake would prevent a large number of incident cases.