Michael Leitzmann received an MD from the University of Berlin and completed an MPH and a DrPH at the Harvard School of Public Health. He subsequently joined the Division of Cancer Epidemiology and Genetics of the US National Cancer Institute as investigator. In 2008, he was appointed Professor and Chair of the Department of Epidemiology and Preventive Medicine at the University of Regensburg, germany. He leads an interdisciplinary team of scientists on research related to epidemiology, biostatistics, bioinformatics, nutritional health, and sociology. A major focus is the relationship between energy balance and cancer. This includes investigations of the independent and joint relations of body mass, physical activity, sedentary behavior, and diet in relation to cancer incidence and survival. The energy balance research is characterized by the development and application of methods to validly measure body composition and energy expenditure in large population-based cohorts. Professor Leitzmann has published more than 200 research articles, serves as editorial board member and reviewer to numerous biomedical journals, and acts as scientific consultant to several national and international advisory boards and research institutions. He is a member of the International Epidemiological Association, the American College of Epidemiology, and the Society for Epidemiologic Research.
Objective: Evidence suggests that diet and lifestyle affect cancer incidence and survival. The WCRF/AICR Continuous Update Project comprehensively summarizes published epidemiologic data regarding such relationships.
Methods: Data are summarized/meta-analyzed using standard methodology and are subsequently independently evaluated by a panel of international scientists.
Results: Liver cancer: based on 34 studies and 24,600 liver cancer cases, there is strong evidence for increased liver cancer risk with overweight/obesity and intakes of alcohol and aflatoxin-contaminated foods. In contrast, there is strong evidence for decreased liver cancer risk with drinking coffee, and limited evidence for decreased liver cancer risk with consuming fish and engaging in physical activity. Gallbladder cancer: data from 14 studies and 8,300 gallbladder cancer cases reveal strong evidence for increased gallbladder cancer risk with overweight/obesity. Prostate cancer: a review of 104 studies and 191,000 cases of prostate cancer shows strong evidence that overweight/obesity are associated with increased risk of advanced prostate cancer. By comparison, consuming beta-carotene is unlikely to substantially affect prostate cancer risk. Also, there is limited evidence for increased prostate cancer risk with high intakes of dairy products and calcium. Stomach cancer: based on 89 studies and 77,000 stomach cancer cases, there is strong evidence for increased risk of stomach cancer with consumption of alcohol and foods preserved by salting. Also, processed meat intake is associated with increased risk of non-cardia stomach cancer, whereas being overweight or obese is related to increased risk of cancer of the cardia. There is limited evidence that consuming grilled or barbecued meat and fish is associated with increased risk of stomach cancer. In addition, there is some evidence to suggest that consuming little or no fruit is related to increased risk of stomach cancer, and that consuming citrus fruit decreases the risk of stomach cardia cancer. Breast cancer survivorship: based on data from 85 studies and 164,416 women, a healthy body weight, physical activity, and greater consumption of fiber and soy are related to increased survival, whereas a diet high in fat and saturated fat before diagnosis is associated with decreased survival. However, the latter findings may be confounded by limitations in the quality of the studies reviewed, which precludes making specific recommendations.
Conclusions: The presentation concludes with a brief summary of future research priorities in the area of diet, nutrition, physical activity and cancer.