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Well, since we've started a thread here on the "General Health and Longevity" forum dedicated to Colon Cancer Prevention, I figured we might as well have one for prostate cancer too, particularly since CR practitioners are overwhelmingly male, and because among US men, prostate cancer is the most common cancer and second leading cancer killer based on CDC Statistics. Plus, there is a new study [1] showing how good my favorite diet (vegan) is for prostate cancer prevention. The study followed ~26,000 men (obviously) who are participating in the famous Adventist Health Study-2, and recruited between 2002 and 2007. It found that men eating a vegan diet were 35% less likely to develop prostate cancer (HR: 0.65; 95% CI: 0.49, 0.85) relative to omnivores during the mean follow-up period of 7.8 year, even after adjusting for age, race, family history of prostate cancer, education, screening for prostate cancer, calorie intake, and BMI. The last is significant because it shows that it wasn't just a result of the vegans being thinner than the omnivores that protected them from prostate cancer. Interestingly, and distinctively from other studies of this population where health benefits relative to omnivores have been observed among all the categories of vegetarians, the benefits observed here for prostate cancer avoidance were entirely restricted to the vegan diet group. Below is the summary table of relative risks for the different diet groups, broken down by race. Looking at data for white men I've highlighted. None of the other vegetarian categories have even a hint of reduction in prostate cancer risk relative to omnivores, not even the pesky pesco-vegetarians - only the vegans: So if you want to avoid the most common form of cancer among men in the US, and the second leading cause of cancer death, go vegan! --Dean -------------- [1] Am J Clin Nutr. 2015 Nov 11. pii: ajcn106450. [Epub ahead of print] Are strict vegetarians protected against prostate cancer? Tantamango-Bartley Y(1), Knutsen SF(2), Knutsen R(2), Jacobsen BK(3), Fan J(2), Beeson WL(2), Sabate J(2), Hadley D(4), Jaceldo-Siegl K(2), Penniecook J(2), Herring P(2), Butler T(2), Bennett H(2), Fraser G(2). BACKGROUND: According to the American Cancer Society, prostate cancer accounts for ∼27% of all incident cancer cases among men and is the second most common (noncutaneous) cancer among men. The relation between diet and prostate cancer is still unclear. Because people do not consume individual foods but rather foods in combination, the assessment of dietary patterns may offer valuable information when determining associations between diet and prostate cancer risk. OBJECTIVE: This study aimed to examine the association between dietary patterns (nonvegetarian, lacto-ovo-vegetarian, pesco-vegetarian, vegan, and semi-vegetarian) and prostate cancer incidence among 26,346 male participants of the Adventist Health Study-2. DESIGN: In this prospective cohort study, cancer cases were identified by matching to cancer registries. Cox proportional hazards regression analysis was performed to estimate HRs by using age as the time variable. RESULTS: In total, 1079 incident prostate cancer cases were identified. Around 8% of the study population reported adherence to the vegan diet. Vegan diets showed a statistically significant protective association with prostate cancer risk (HR: 0.65; 95% CI: 0.49, 0.85). After stratifying by race, the statistically significant association with a vegan diet remained only for the whites (HR: 0.63; 95% CI: 0.46, 0.86), but the multivariate HR for black vegans showed a similar but nonsignificant point estimate (HR: 0.69; 95% CI: 0.41, 1.18). CONCLUSION: Vegan diets may confer a lower risk of prostate cancer. This lower estimated risk is seen in both white and black vegan subjects, although in the latter, the CI is wider and includes the null. © 2016 American Society for Nutrition. PMID: 26561618

All, Al Pater posted this paper [1] on the mortality rates of meat-eaters vs. vegetarians (and vegans) among participates in the EPIC-Oxford study of diet and health. The results were disappointing for us vegans (and vegetarians): There was no significant difference in overall (all-cause) mortality between the diet groups: HRs in low meat eaters, fish eaters, and vegetarians compared with regular meat eaters were 0.93 (95% CI: 0.86, 1.00), 0.96 (95% CI: 0.86, 1.06), and 1.02 (95% CI: 0.94, 1.10), respectively; P-heterogeneity of risks = 0.082. In a separate sub-analysis of the vegan's in the study, they found the same thing - no difference in all-cause mortality between vegans and any of the other diets. Given the distinct longevity advantage for vegans and vegetarians seen in the Adventists Health Study [2], what's the deal with these British vegans and vegetarians? One possible reason is social support. From the demographics in Table 1 of the full text of [1], the UK vegans and vegetarians were significantly less likely to be married or cohabitating than meat eaters (60.8% vs. 75.5%), and less likely to have kids (41.5% vs. 77.2%). Loneliness and social isolation are well-known contributors to ill-health and early mortality. In contrast, from the full text of [2], the Adventist vegans were slightly more likely to be married than the meat-eaters (75.6% vs. 70.3%). In addition, study [3] found the vegetarians and especially vegans in the Epic-Oxford study have significantly lower levels of vitamin B12 than meat-eaters, to the point of outright deficiency: Half of the vegans were categorized as vitamin B12 deficient and would be expected to have a higher risk of developing clinical symptoms related to vitamin B12 deficiency. Here is the graph of B12 levels in meat-eaters (open circles at top), vegetarians (closed circles in middle) and vegans (open triangles at bottom): So perhaps it is low B12 and/or other specific vitamin deficiencies among poorly planned diets of the EPIC-Oxford vegan / vegetarian participants that make them more prone to dying than the Adventists. Or perhaps it is simply overall diet quality that is worse in the UK vegans/vegetarians relative to the Adventists that makes them shorter-lived. Here is the table with diet information for the EPIC-Oxford cohort from [1]: As you can see from the highlights in yellow, the vegans/vegetarians aren't much better than the meat eaters in terms of dietary saturated fat, fiber, fruit or vegetable intake. This contrasts markedly with the Adventists dietary data, from [4], shown in tabular form below: Notice among the Adventists, the vegans consumed 50% more fiber and about have the saturated fat compared with the Adventist meat-eaters, and over twice as much fiber as the vegans/vegetarians in the EPIC-Oxford cohort. Unfortunately, the table does not have explicit data on fruit or vegetable consumption, but the fiber numbers and higher Vitamin C numbers of vegans are probably a pretty good indication of higher consumption of fruits/veggies among the vegans. Also notice that B12 intake is actually higher for vegans than for meat-eaters among the Adventist, presumably due to supplementation by the vegans. So overall, it looks the the answer to the question in the title of this post, "Why Don't UK Vegans/Vegetarians Live Longer?", is likely to be that they have much lower overall diet quality than more carefully planned vegan and vegetarian diets, like those of the Adventists, and (hopefully) all of us CR practitioners! This comparison could also be thought of as support for the idea that dietary quality may be as important or more important for health and longevity than dietary quantity (i.e. CR), which I posted about yesterday, and previously in the context of comparing the Okinawans with the Adventists. --Dean ------ [1] Mortality in vegetarians and comparable nonvegetarians in the United Kingdom. Appleby PN, Crowe FL, Bradbury KE, Travis RC, Key TJ. Am J Clin Nutr. 2015 Dec 9. pii: ajcn119461. [Epub ahead of print] PMID: 26657045 Free Article http://ajcn.nutrition.org/content/early/2015/12/07/ajcn.115.119461.long Abstract BACKGROUND: Vegetarians and others who do not eat meat have been observed to have lower incidence rates than meat eaters of some chronic diseases, but it is unclear whether this translates into lower mortality. OBJECTIVE: The purpose of this study was to describe mortality in vegetarians and comparable nonvegetarians in a large United Kingdom cohort. DESIGN: The study involved a pooled analysis of data from 2 prospective studies that included 60,310 persons living in the United Kingdom, comprising 18,431 regular meat eaters (who ate meat =5 times/wk on average), 13,039 low (less-frequent) meat eaters, 8516 fish eaters (who ate fish but not meat), and 20,324 vegetarians (including 2228 vegans who did not eat any animal foods). Mortality by diet group for each of 18 common causes of death was estimated with the use of Cox proportional hazards models. RESULTS: There were 5294 deaths before age 90 in >1 million y of follow-up. There was no significant difference in overall (all-cause) mortality between the diet groups: HRs in low meat eaters, fish eaters, and vegetarians compared with regular meat eaters were 0.93 (95% CI: 0.86, 1.00), 0.96 (95% CI: 0.86, 1.06), and 1.02 (95% CI: 0.94, 1.10), respectively; P-heterogeneity of risks = 0.082. There were significant differences in risk compared with regular meat eaters for deaths from circulatory disease [higher in fish eaters (HR: 1.22; 95% CI: 1.02, 1.46)]; malignant cancer [lower in fish eaters (HR: 0.82; 95% CI: 0.70, 0.97)], including pancreatic cancer [lower in low meat eaters and vegetarians (HR: 0.55; 95% CI: 0.36, 0.86 and HR: 0.48; 95% CI: 0.28, 0.82, respectively)] and cancers of the lymphatic/hematopoietic tissue [lower in vegetarians (HR: 0.50; 95% CI: 0.32, 0.79)]; respiratory disease [lower in low meat eaters (HR: 0.70; 95% CI: 0.53, 0.92)]; and all other causes [lower in low meat eaters (HR: 0.74; 95% CI: 0.56, 0.99)]. Further adjustment for body mass index left these associations largely unchanged. CONCLUSIONS: United Kingdom-based vegetarians and comparable nonvegetarians have similar all-cause mortality. Differences found for specific causes of death merit further investigation. KEYWORDS: diet; mortality; nonvegetarian; vegan; vegetarian -------- [2] [2] JAMA Intern Med.. 2013 Jul 8;173(13):1230-8.. doi: 10.1001/jamainternmed.2013.6473. Vegetarian dietary patterns and mortality in Adventist Health Study 2. Orlich MJ(1), Singh PN, Sabaté J, Jaceldo-Siegl K, Fan J, Knutsen S, Beeson WL, Fraser GE. Author information: (1)School of Public Health, Loma Linda University, Loma Linda, CA 92350, USA. morlich@llu.edu Comment in JAMA Intern Med.. 2014 Jan;174(1):168-9. JAMA Intern Med.. 2014 Jan;174(1):169. JAMA Intern Med.. 2013 Jul 8;173(13):1238-9. Dtsch Med Wochenschr.. 2013 Sep;138(39):1930. IMPORTANCE: Some evidence suggests vegetarian dietary patterns may be associated with reduced mortality, but the relationship is not well established. OBJECTIVE: To evaluate the association between vegetarian dietary patterns and mortality. DESIGN: Prospective cohort study; mortality analysis by Cox proportional hazards regression, controlling for important demographic and lifestyle confounders. SETTING: Adventist Health Study 2 (AHS-2), a large North American cohort. PARTICIPANTS: A total of 96,469 Seventh-day Adventist men and women recruited between 2002 and 2007, from which an analytic sample of 73,308 participants remained after exclusions. EXPOSURES: Diet was assessed at baseline by a quantitative food frequency questionnaire and categorized into 5 dietary patterns: nonvegetarian, semi-vegetarian, pesco-vegetarian, lacto-ovo-vegetarian, and vegan. MAIN OUTCOME AND MEASURE: The relationship between vegetarian dietary patterns and all-cause and cause-specific mortality; deaths through 2009 were identified from the National Death Index. RESULTS: There were 2570 deaths among 73,308 participants during a mean follow-up time of 5.79 years.. The mortality rate was 6.05 (95% CI, 5.82-6.29) deaths per 1000 person-years.. The adjusted hazard ratio (HR) for all-cause mortality in all vegetarians combined vs nonvegetarians was 0.88 (95% CI, 0.80-0.97).. The adjusted HR for all-cause mortality in vegans was 0.85 (95% CI, 0.73-1.01); in lacto-ovo-vegetarians, 0.91 (95% CI, 0.82-1.00); in pesco-vegetarians, 0.81 (95% CI, 0.69-0.94); and in semi-vegetarians, 0.92 (95% CI, 0.75-1.13) compared with nonvegetarians.. Significant associations with vegetarian diets were detected for cardiovascular mortality, noncardiovascular noncancer mortality, renal mortality, and endocrine mortality.. Associations in men were larger and more often significant than were those in women. CONCLUSIONS AND RELEVANCE: Vegetarian diets are associated with lower all-cause mortality and with some reductions in cause-specific mortality.. Results appeared to be more robust in males.. These favorable associations should be considered carefully by those offering dietary guidance. PMCID: PMC4191896 PMID: 23836264 ----------- [3] Eur J Clin Nutr. 2010 Sep;64(9):933-9. doi: 10.1038/ejcn.2010.142. Epub 2010 Jul 21. Serum concentrations of vitamin B12 and folate in British male omnivores, vegetarians and vegans: results from a cross-sectional analysis of the EPIC-Oxford cohort study. Gilsing AM(1), Crowe FL, Lloyd-Wright Z, Sanders TA, Appleby PN, Allen NE, Key TJ. Author information: (1)Cancer Epidemiology Unit, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK. BACKGROUND/OBJECTIVES: Vegans, and to a lesser extent vegetarians, have low average circulating concentrations of vitamin B12; however, the relation between factors such as age or time on these diets and vitamin B12 concentrations is not clear. The objectives of this study were to investigate differences in serum vitamin B12 and folate concentrations between omnivores, vegetarians and vegans and to ascertain whether vitamin B12 concentrations differed by age and time on the diet. SUBJECTS/METHODS: A cross-sectional analysis involving 689 men (226 omnivores, 231 vegetarians and 232 vegans) from the European Prospective Investigation into Cancer and Nutrition Oxford cohort. RESULTS: Mean serum vitamin B12 was highest among omnivores (281, 95% CI: 270-292 pmol/l), intermediate among vegetarians (182, 95% CI: 175-189 pmol/l) and lowest among vegans (122, 95% CI: 117-127 pmol/l). In all, 52% of vegans, 7% of vegetarians and one omnivore were classified as vitamin B12 deficient (defined as serum vitamin B12 <118 pmol/l). There was no significant association between age or duration of adherence to a vegetarian or a vegan diet and serum vitamin B12. In contrast, folate concentrations were highest among vegans, intermediate among vegetarians and lowest among omnivores, but only two men (both omnivores) were categorized as folate deficient (defined as serum folate <6.3 nmol/l). CONCLUSION: Vegans have lower vitamin B12 concentrations, but higher folate concentrations, than vegetarians and omnivores. Half of the vegans were categorized as vitamin B12 deficient and would be expected to have a higher risk of developing clinical symptoms related to vitamin B12 deficiency. PMCID: PMC2933506 PMID: 20648045 ------------ [4] J Acad Nutr Diet. 2013 Dec;113(12):1610-9. doi: 10.1016/j.jand.2013.06.349. Epub 2013 Aug 27. Nutrient profiles of vegetarian and nonvegetarian dietary patterns. Rizzo NS, Jaceldo-Siegl K, Sabate J, Fraser GE. Comment in J Acad Nutr Diet. 2014 Feb;114(2):197-8. J Acad Nutr Diet. 2014 Feb;114(2):197. BACKGROUND: Differences in nutrient profiles between vegetarian and nonvegetarian dietary patterns reflect nutritional differences that can contribute to the development of disease. OBJECTIVE: Our aim was to compare nutrient intakes between dietary patterns characterized by consumption or exclusion of meat and dairy products. DESIGN: We conducted a cross-sectional study of 71,751 subjects (mean age=59 years) from the Adventist Health Study 2. Data were collected between 2002 and 2007. Participants completed a 204-item validated semi-quantitative food frequency questionnaire. Dietary patterns compared were nonvegetarian, semi-vegetarian, pesco vegetarian, lacto-ovo vegetarian, and strict vegetarian. Analysis of covariance was used to analyze differences in nutrient intakes by dietary patterns and was adjusted for age, sex, and race. Body mass index and other relevant demographic data were reported and compared by dietary pattern using χ(2) tests and analysis of variance. RESULTS: Many nutrient intakes varied significantly between dietary patterns. Nonvegetarians had the lowest intakes of plant proteins, fiber, beta carotene, and magnesium compared with those following vegetarian dietary patterns, and the highest intakes of saturated, trans, arachidonic, and docosahexaenoic fatty acids. The lower tails of some nutrient distributions in strict vegetarians suggested inadequate intakes by a portion of the subjects. Energy intake was similar among dietary patterns at close to 2,000 kcal/day, with the exception of semi-vegetarians, who had an intake of 1,707 kcal/day. Mean body mass index was highest in nonvegetarians (mean=28.7 [standard deviation=6.4]) and lowest in strict vegetarians (mean=24.0 [standard deviation=4.8]). CONCLUSIONS: Nutrient profiles varied markedly among dietary patterns that were defined by meat and dairy intakes. These differences are of interest in the etiology of obesity and chronic diseases. Copyright © 2013 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved. PMCID: PMC4081456 PMID: 23988511