Lower Cancer Rates in Vegans
The Oxford arm of the European Prospective Investigations Into Cancer (EPIC) has released a report showing that after an average of 14.9 years of follow-up, vegetarians (.88, .82-.95) and pesco-vegetarians (.88, .80-.97) each have a 12% lower risk of cancer than other meat-eaters (1).
Breaking the participants into smaller diet groups showed that vegans had a 19% lower risk of cancer:
Pesco – .88 (.80, .97)
Lacto-ovo – .89 (.83, .96)
Vegan – .81 (.66, .98)
I have updated the General Cancer section of the VeganHealth.org article, Cancer, Vegetarianism, and Diet. If you go there, you can see that the findings for vegans were similar to those in the Adventist Health Study-2 (AHS-2), the other ongoing study containing a large number of vegans.
Unlike the findings for vegans and diabetes, the statistical significance of these findings for cancer are not large. I like confidence intervals to be tighter before I get too excited about saying a vegan diet can prevent a disease. However, the consistency between EPIC-Oxford and AHS-2 should provide some assurance.
Some notes on these findings:
– The results above are not adjusted for body mass index (BMI). Adjusting for BMI slightly changed the findings for vegetarians (.90, .93-.96) and for vegans (.82, .68-1.00).
– The previous report from EPIC-Oxford had followed participants through 2005 while this current report followed them through 2010. In the intervening years, cancers increased 50%.
– Diets were assessed at baseline and after 5 years; 88% of the participants remained in their original diet category.
– No single specific cancer type could explain the differences between the diet groups; to date there has been very little consistency found between the various cancers (such as colorectal) and diet group.
1. Key TJ, Appleby PN, Crowe FL, Bradbury KE, Schmidt JA, Travis RC. Cancer in British vegetarians: updated analyses of 4998 incident cancers in a cohort of 32,491 meat eaters, 8612 fish eaters, 18,298 vegetarians, and 2246 vegans. Am J Clin Nutr. 2014 Jun 4. | link