Not All Dietary Fibers Are Equal for Lowering Colorectal Cancer Risk

Whole grain and cereal fibers were linked with lower risk; fruits, vegetables, and legumes were not.

The association between dietary fiber intake and colorectal cancer risk is unclear. In a meta-analysis of 25 prospective observational studies that involved nearly 2 million people, investigators assessed this association.


Participants' daily fiber intake ranged from 6 to 21 g for total fiber, 2 to 16 g for fruit fiber, 2 to 17 g for vegetable fiber, 3 to 17 g for cereal fiber, and 1 to 4 g for legume fiber. Daily whole grain intake ranged from 61 g to 128 g. Participants with high total fiber intake had 12% lower risk for colorectal cancer than those with low total fiber intake. When intake was analyzed by fiber type, people with high cereal fiber intake had 10% lower risk, and those with high whole grain intake had 21% lower risk, than people with low intakes of these fibers. Dose–response relations were observed for each of these fiber types. In contrast, intake of fiber from fruits, vegetables, or legumes did not affect colorectal cancer risk.


Citation(s):

Aune D et al. Dietary fibre, whole grains, and risk of colorectal cancer: Systematic review and dose-response meta-analysis of prospective studies. BMJ 2011 Nov 10; 343:d6617.