Mortality in British vegetarians.
Level 3 - non-randomized controlled study
Prospective cohort study analyzing mortality across two cohorts
PubMed 12001975 · doi:10.1079/PHN2001248
What was done
Original data from two UK prospective cohort studies—the Oxford Vegetarian Study and the Health Food Shoppers Study—were analyzed. The cohorts comprised 21,000 men and women aged 16–89 at recruitment, including more than 8,000 vegetarians. Standardised mortality ratios (SMRs) for deaths occurring before age 90 were calculated relative to the general population of England and Wales. Within each cohort, death rate ratios (DRRs) comparing vegetarians to non-vegetarians were calculated for all-cause mortality and 14 major causes of death.
What was found
Compared to the general population, all-cause mortality was substantially lower in both cohorts: SMR was 52 (95% CI 49–56; 1,131 deaths) in the Oxford Vegetarian Study and 59 (95% CI 57–61; 2,346 deaths) in the Health Food Shoppers Study. However, within-study comparisons showed no difference in all-cause mortality between vegetarians and non-vegetarians: the DRR was 1.01 (95% CI 0.89–1.14) in the Oxford Vegetarian Study and 1.03 (95% CI 0.95–1.13) in the Health Food Shoppers Study.
Why it matters
These findings suggest that the survival advantage of vegetarians relative to the general public is largely shared with comparable health-conscious non-vegetarians, pointing to confounding by lifestyle factors such as low smoking rates or higher socioeconomic status rather than meat avoidance per se.
Limits
As an observational study, residual confounding cannot be ruled out. The abstract does not report specific numerical risk estimates for the 14 individual causes of death examined. The cohorts recruited health-conscious individuals and health food shoppers in the UK, which may limit generalizability to other populations.
Cited by
- supports The UK Shopper Study found that meat eaters and vegetarians had similar rates of all-cause mortality when healthy behaviors in vegetarians were accounted for.