Prevention Strategies for Inflammatory Bowel Disease

Ulcerative colitis (UC) and Crohn's disease (CD) are well-known representative forms of inflammatory bowel disease (IBD) and they have long been regarded as intractable diseases of unknown etiology. Recent advances in genomic analyses, immunology, studies of the intestinal microbiota, elucidation of environmental factors, and long-term human cohort studies have greatly improved our understanding of the disease pathogenesis and accelerated the development of preventive approaches. Historically, the incidence of IBD was the highest in Western countries; however, in recent years, the number of patients in newly industrialized countries has increased rapidly. Therefore, the establishment of active strategies aimed at preventing disease onset has become extremely important, in addition to the development of new therapeutic agents. This review summarizes the most recent findings regarding the etiology of IBD obtained mainly from human cohort studies and discusses the current efforts directed toward prevention and early intervention, with particular emphasis on the importance of dietary and nutritional factors.