Cancer incidence among Danish Seventh-day Adventists and Baptists

Introduction: American Seventh-day Adventists have been reported to have lower cancer mortality and incidence than the general population. Adventists do not consume tobacco, alcohol or pork, and many adhere to a lacto-ovo-vegetarian lifestyle. Baptists discourage excessive use of alcohol and tobacco. In this study, we investigated whether the incidence of cancer in a large cohort of Danish Adventists and Baptists was different compared to the general Danish population.

Material and methods: We followed 11,580 Danish Adventists and Baptists in the nationwide Danish Cancer Registry, which contains information on cases of cancer for 1943-2008. Cancer incidence in the cohort was compared with that in the general Danish population as standardized incidence ratios (SIRs) with 95% confidence intervals (CIs), and within-cohort comparisons were made with a Cox model.

Results: Lower cancer incidences were observed for both Seventh-day Adventist men (SIR, 66; 95% CI, 60-72) and women (85; 80-91). The same result was observed for Baptists although not as low. The differences were most pronounced for smoking-related cancers such as those of the buccal cavity and lung (SIR, 20; 13-30 for Seventh-day Adventist men and 33; 22-49 for Seventh-day Adventist women). The incidences of other lifestyle-related cancers, such as of stomach, rectum, liver and cervix, were also decreased. In general, the SIRs were lower for men than for women, and Adventists had lower hazard rates than Baptists.

Discussion: Our findings point to the benefits of compliance with public health recommendations and indicate that lifestyle changes in the population might change the cancer risks of individuals.