Mortality in vegetarians and nonvegetarians: detailed findings from a collaborative analysis of 5 prospective studies. Key TJ, Fraser GE, Thorogood M, Appleby PN, Beral V, Reeves G, Burr ML, Chang-Claude J, Frentzel-Beyme R, Kuzma JW, Mann J, McPherson K. Am J Clin Nutr. 1999 Sep;70(3 Suppl):516S-524S. [FREE FULL TEXT]
We combined data from 5 prospective studies to compare the death rates from common diseases of vegetarians with those of nonvegetarians with similar lifestyles. A summary of these results was reported previously; we report here more details of the findings. Data for 76172 men and women were available. Vegetarians were those who did not eat any meat or fish (n = 27808). Death rate ratios at ages 16-89 y were calculated by Poisson regression and all results were adjusted for age, sex, and smoking status. A random-effects model was used to calculate pooled estimates of effect for all studies combined. There were 8330 deaths after a mean of 10.6 y of follow-up. Mortality from ischemic heart disease was 24% lower in vegetarians than in nonvegetarians (death rate ratio: 0.76; 95% CI: 0.62, 0.94; P<0.01). The lower mortality from ischemic heart disease among vegetarians was greater at younger ages and was restricted to those who had followed their current diet for >5 y. Further categorization of diets showed that, in comparison with regular meat eaters, mortality from ischemic heart disease was 20% lower in occasional meat eaters, 34% lower in people who ate fish but not meat, 34% lower in lactoovovegetarians, and 26% lower in vegans. There were no significant differences between vegetarians and nonvegetarians in mortality from cerebrovascular disease, stomach cancer, colorectal cancer, lung cancer, breast cancer, prostate cancer, or all other causes combined.
Either my social circle has been expanding to include more vegetarians as of late or since I’m interested in intermittent fasting, the health attributes of different diets comes up more in conversation. Though, this is an older study it does seem to be the most comprehensive paper on longevity with vegetarian diets and it went so far as to sort out the different types. It does seem really hard to tell what works best with all the factors involved, but it does seem that eating a lot of red meat isn’t the greatest, reducing the eating of meat to less than once a week seems better. Being a lacto-ovo vegetarian (eats dairy and eggs) and or being a pescetarian (dairy, eggs, plus fish) seem to be the sweet spot for health.
Excluding all animal products might be great for moral reasons, and though it reduces mortality due to heart disease; all cause mortality, it was not reduced compared to regular meat eaters. Interestingly, and not clear from the abstract, all cause mortality was rated at 1.00 for regular meat eaters, 0.84 for occasional meat eaters, 0.82 for pescetarians, 0.84 for lacto-ovo vegetarians, and back up to 1.00 for vegans, per table 7 of the study.
Perhaps meaningful caveats to this study are that there were fewer vegans (753) in the study vs 2375 fish eaters and 23,265 lacto-ovo vegetarians, and per the vegan website where I found this study, a lot of the data was taken before the importance of B12 supplementation for vegans was known. Still, per the data thus far, it seems there is some benefit to including dairy, eggs and fish in your diet. As for veganism, one remaining benefit is you should still get the subtle nods of approval from every passing animal. So far I’m still appreciating the benefits of my intermittent fasting where I can eat as much as I want, of anything I want, just not always whenever I want. It does make me wonder what would happen if you combined intermittent fasting with a lacto-ovo or pescetarian diet, would you become immortal or would it be too much of a good thing?
As always, if you have any further questions or need for clarifications, please don’t hesitate to ask. Being aware that some of my blog ideas are contentious and occasionally a bit out of the field of my expertise, I encourage my readers to come forth with any questions/comments that are of interest or concern. Your comments are valued and welcomed.
Chad Reilly is a licensed physical therapist, located in North Phoenix, practicing science based medicine with treatment protocols unique and effective enough to proudly serve patients from Phoenix, Scottsdale, Mesa, Chandler, Tempe, Peoria, and Glendale.