Topic Explanation:
The discussion in the forum revolves around the question of how much of the colon can be removed without causing major health issues, and what the implications might be for life post-surgery, particularly concerning the feasibility of a reversal surgery. The original poster is concerned about the outcomes of having a significantly shortened colon, including the potential need for dialysis, frequent bathroom visits, or the necessity of an ileostomy.

Extracted Advice and Helpful Insights:
1. Extent of Colon Removal and Reversal Feasibility:
- It is possible to have the entire colon removed and still undergo a successful reversal using a J-pouch, provided the anal sphincter is intact and functional. This typically results in using the bathroom around 6 times a day after about a year of adjusting to the J-pouch.
- In cases where the rectum or rectal stump is left intact and is disease-free, it can offer more storage capacity than a J-pouch alone, potentially reducing the frequency of bathroom visits to 2-3 times a day with the aid of medications like Imodium or Lomotil.

2. Information and Decision Making:
- It is crucial to ask many questions and understand both the positive and negative aspects of the surgery and its aftermath. Some participants noted a lack of comprehensive information from doctors, emphasizing the importance of being proactive and relentless in seeking detailed explanations.

3. J-Pouch Specifics:
- A J-pouch is an internal reservoir created from the small intestine, connected to the rectal stump, allowing stool to be stored temporarily. This setup helps in avoiding an external pouch but may require frequent bathroom visits (5-9 times a day), and continence can vary based on individual factors such as diet and sphincter control.
- The J-pouch can have complications like pouchitis or the need for re-surgery, and it is not suitable for patients with Crohn's disease as it can be mistaken for ulcerative colitis initially.

4. Comparisons with Ileostomy:
- An ileostomy involves creating a stoma for waste to exit the body into an external pouch, which might be simpler and have fewer complications compared to a J-pouch. However, it also involves managing an external appliance and can have issues like food blockages and skin irritation.

5. Personal Experiences and Outcomes:
- Experiences with both J-p