抄録
Dietary factors are estimated to account for approximately 30% of cancer deaths in the United States. According to a WHO/FAO report in 2003 based on a review of published epidemiological studies, convincing evidence linking diet-related factors and cancer is available for the following associations: physical activity (colorectal cancer), overweight/obesity (cancers of esophagus <adenocarcinoma>, colorectum, breast <postmenopausal>, endometrium and kidney), alcohol (cancers of oral cavity, pharynx, esophagus, liver and breast), aflatoxin (liver) and Chinese-style salted fish (nasopharyngeal cancer). Fruits and vegetables (cancers of oral cavity, esophagus, stomach and colorectum) and physical activity (breast cancer) probably reduce the risk, while preserved and red meat (colorectal cancer), salt-preserved foods and high salt intake (stomach cancer) and very hot drinks and foods (cancers of oral cavity, pharynx and esophagus) probably increase the risk. Since these evidences are mainly based on epidemiological studies in Western countries, more evidence from studies in Japan is essential to establish appropriate recommendations for reducing the risk of developing cancer among Japanese. Recent information from the Japan Public Health Centerbased prospective study (JPHC Study), on-going population-based cohort study in 11 areas nationwide, is providing evidence for the association between dietary factors and the risk of gastric and breast cancers.