The following major studies are available:
- The majority of case-controlled studies conducted before 1990 found a correlation between higher fiber intake and a lower incidence of colorectal cancer; (2, 3)
- Most prospective cohort studies have not found a correlation between dietary fiber and colorectal cancer; (1)
- A combined analysis of 13 prospective cohort studies involving over 700,000 adults have not found a correlation between high dietary fiber intake and colorectal cancer; (4)
- The largest prospective study involving over half a million men and women has shown that dietary fiber reduces the risk of colon cancer; (5) Four controlled clinical trials did not find evidence of correlation between the diet high in fiber, fruit and vegetables and low in fat with the risk of recurrence of colorectal adenomas. (6)
These studies are believed to have given different results due to following possible reasons(1):
- Inadequate type or amount of fiber used in the studies to prevent cancer incidence;
- Other dietary factors that might have interfered with the fiber action;
- Other components in the diet that could have been responsible for some results;
- In the observational studies potentially incorrect methods for assessing fiber intake were used.
NUTRITION FACTS VS NUTRITION MYTHS
You will find a summary of the most common nutrition myths and evidence-based nutrition facts here.