The cancer-prevention properties of dietary fiber are hardly a secret. Indeed, in modern times, the late Dr. Denis Burkitt (of Burkitt lymphoma fame) made the fiber story famous from his work among native Africans.^[1] This British researcher, with his colleagues Alan Walker and Hugh Trowell, spent many years in Africa tirelessly working to better understand why diseases typically found in Western countries were rare in Africa. What he discovered made worldwide news. Diets high in fiber appeared to be associated with reduced cancer incidence of the large bowel, as well as the incidence of many other diseases common to Western countries.^[2][3]

Looking at the Big Picture

In rural China, we took this lead to explore the fiber-cancer association among people consuming much more fiber than Americans.^[4] In so doing, we incorporated two other understandings. First, dietary fiber is not a single chemical entity. There is an almost unlimited variety of dietary fibers. Second, our knowledge about the unique effects of specific fibers was, and still is, very sparse. To better capture the big picture, we measured the consumption of 14 different kinds of dietary fiber.

As expected, we first noted that the average dietary fiber intake in rural China was at least double, perhaps even triple, that in the US. Second, the rates of colon and rectal cancers in China were only about one-half the rates in the US, although in some areas, this cancer was almost nonexistent.

Also as expected, we did not see any special differences in the cancer-related effects of these different fibers. We found inverse correlations for each of the 14 fiber types (although almost all of these correlations were somewhat less than statistically significant): the higher the fiber intake, the lower the rates of colon and rectal cancers.

In conclusion, our view is that Burkitt’s dietary fiber theory remains intact. It is worthwhile to consume high-fiber diets not only to prevent large bowel cancers but also to promote numerous other positive health conditions. And finally, remember that dietary fiber can only be found in foods of plant origin, once again pointing to the value of consuming plant-based diets.

References

1. Cummings JH, Engineer A. Denis Burkitt and the origins of the dietary fibre hypothesis. Nutr Res Rev. 2018;31(1):1-15. doi:10.1017/S0954422417000117
2. Burkitt DP. Epidemiology of cancer of the colon and rectum. Cancer. 1971;28(1):3-13. doi:10.1002/1097-0142(197107)28:1<3::aid-cncr2820280104>3.0.co;2-n
3. Burkitt DP. Western diseases and their emergence related to diet. S Afr Med J. 1982;61(26):1013-1015.
4. Chen J, Campbell TC, Li J, et al. Diet, life-style and mortality in China. A study of the characteristics of 65 Chinese counties. Oxford, UK; Ithaca, NY; Beijing, PRC: Oxford University Press; Cornell University Press; People’s Medical Publishing House, 1990.