Does flax seed or green tea prevent colorectal cancer?

Not known. Though the supposed health benefits of these are touted, there is no definitively known knowledge that it will prevent any type of cancer.

Related Questions

How does reducing colonic transit time with fiber prevent colorectal cancer?

It doesnt. That was antheory espoused several years ago based on population based studies but it never panned out.
Inflammation! Although the data supports a healthy diet high in fiber with fruits and vegetables improves colonic health - there is some speculation that it may also reduce the risk of colorectal cancer. A diet high in dietary fiber reduces colonic transit time - meaning you go more regularly. The more regular you move your bowels there is less stagnation of stool and decreased inflammation in the colon.
Less contact. The hypothesis is that one factor in colon cancer is potentially ingested carcinogens (cancer causing) that are in the food we eat. The faster the stool moves through the colon, the less time the carcinogen has in contact with any segment of the colon so it's should be less damaging.

What diet should I follow to prevent colorectal cancer from occurring?

Eat your veggies. Population studies show groups that eat high fiber, grains, fruit, veggies, legumes have lower rates. Calcium foods (no/low fat dairy), may help. Low intake meat, especially processed meats may help. Fiber supplements are less helpful than fiber foods. Low (sat) fat, high fiber may be a good combo. Dash diet (dietary approach to stop hypertension): easy, tasty, healthy. Find it online.
Colon CA & Diet. Colon cancer has been associated with diets high in animal fat, red meats, and processed meats containing nitrites. Eating a well balanced diet that minimizes these foods, and contains leafy, green vegetables, and foods high in antioxidants, minerals, and vitamins, is recommended to decrease the risk. Dietary fiber is also recommended to reduce the risk of colorectal cancer.

Is there any way to help prevent the return of my colorectal cancer?

4-Tiered Strategy. Surveillance: at the advice of your gastroenterologist, schedule routine colonoscopies; healthy habits: follow a diet high in veggies, fruits, and whole-grains, try to limit red meat and alcohol, exercise regularly; chemoprevention: talk to your oncologist about taking folate (folic acid) supplements and/or nsaids; genetic testing: if you have many relatives with colon ca, you may be a candidate for testing.