A large prospective Christian-based cohort study from the National Cancer Institute and the World Cancer Research Fund showed that vegetarians have a lower risk of colorectal cancer compared to non-vegetarians, with a statistically significant 22% reduction in incidence. More interestingly, Orlich et al. found that fish vegetarians (those who had consumed fish for more than 1 month but not other meats) had a more significant reduction in the risk of colorectal cancer (43% reduction) compared to other non-vegetarians, a statistically significant difference that should not be attributed to chance. (Dr. Orlich explained that the study recruited American Christians who had previously participated in clinical studies and had more health advantages than the general U.S. citizenry, including longer life span and lower incidence rates. In addition, a higher percentage of these Christians were vegetarians compared to the general population, making them more suitable for studies of vegetarian, low-meat, and high-meat diets and tumor risk. It should be noted, however, that the non-vegetarians in this clinical trial were still relatively low-meat dieters, consuming an average of 2 ounces of meat per day, so the investigators compared vegetarians with relatively low-meat vegetarians and relatively healthy people. In fact, after the researchers corrected for age, race, and gender, the relative risk ratio for colorectal cancer prevalence among non-vegetarians relative to the overall U.S. population was 0.73. This difference is more pronounced if we compare vegetarians to the general population. The prospective cohort study named Christian Health Study-2 included more than 96,000 Christians from January 2002 to December 2007, but the researchers analyzed a total of 77,659 Christians from June to October 2014 to explore the association between vegetarianism as a dietary approach and the risk of colorectal cancer. The food frequency questionnaire was used to evaluate the baseline level of the diet, including non-vegetarians, and divided the vegetarian diet into four categories: first, strict vegetarians (no meat, dairy products or eggs); second, dairy vegetarians (no meat, dairy and eggs allowed); third, fish vegetarians (ever consumed fish for more than 1 month but no other meat); and fourth The fourth group was semi-vegetarians (meat eaten more than once a month but not more than once a week), and colorectal cancer incidence was diagnosed according to the US Tumor Registry. Compared with non-vegetarians, vegetarians were older, more educated, participated in more exercise, took more calcium supplements, smoked less, drank less alcohol, had frequent colonoscopies, took more aspirin or statins, were treated for diabetes in the previous year, and had a history of peptic ulcers more often. (including fresh meat and meat products), and high intake of vegetarian fiber. In this study, 380 of the subjects developed colon cancer and 110 developed rectal cancer during a 7.3-year follow-up. Statistical analysis showed that vegetarian diets were associated with a reduction in the overall incidence of colorectal cancer, with a 19% reduction in the incidence of colon cancer and a 29% reduction in the incidence of rectal cancer; four types of vegetarian habits were associated with a reduced risk of overall colorectal cancer incidence: strict vegetarians (HR=0.84, 95% CI 0.59-1.19), vegetarians who consumed dairy products (HR=0.82, 95% CI 0.65 to 1.02), fish vegetarians (HR=0.57, 95% CI 0.40 to 0.82), and semi-vegetarians (HR=0.92, 95% CI 0.62 to 1.37). Professor Ting-Yuan David Cheng of Roswell Park Cancer Institute noted that the study provides new evidence that fish vegetarians or those who eat a fish-rich diet (a specific type of vegetarian diet) can reduce the risk of colorectal cancer. At the same time, Dr. Cheng said that the study is a well-designed prospective cohort study with several advantages, such as good homogeneity of the subjects included, which reduces bias from other risk factors for colorectal morbidity; and he added (although this is not explicitly stated by the authors) that the results of the study suggest that we may need to act quickly to adhere to and promote this dietary pattern for 20 years Perhaps by the time they are 60 or 70 years old they will be able to witness the benefits of reducing or preventing colorectal morbidity.