There is no way to prevent Crohn's disease.
But you can keep the condition from taking a heavy toll on your body. Maintain a well-balanced, nutritious diet to store up vitamins and nutrients between episodes or flare-ups. By doing so, you can decrease complications from poor nutrition, such as weight loss or anemia.
Also, do not smoke. Along with many other harmful health effects, smoking reduces the risk of getting Crohn's disease and probably makes flare-ups happen more frequently.
Crohn's disease can increase your risk of getting colon cancer. Have your colon checked regularly for early cancerous or precancerous changes. If you have had Crohn's disease affecting the colon or rectum for eight years or more, start getting regular colonoscopies. Have a colonoscopy exam every one to two years once you start regular testing.