Left ventricular diastolic abnormalities in vegetarians compared with non-vegetarians.

Vegetarians have less hypertension, diabetes mellitus and obesity, hence possibly lower risk of congestive heart failure (HF). We studied associations between vegetarian diets and echocardiographic markers of stage B HF. In a cross-sectional study, dietary pattern was ascertained by a validated FFQ. Echocardiograms were interpreted using standardised criteria. Participants were free-living subjects in Southern California who were older Adventist Health Study-2 cohort members. After exclusions, 133 subjects aged >60 years were enrolled. Their mean age was 72·7 (sd 8·7) years, 48·1 % were female, 32 % were African American and 71 % were vegetarian. Non-vegetarians had higher body weight (80·3 (sd 15·17) kg v. 71·3 (sd 16·2), P < 0·005), body surface area (1·92 (sd 0·24) m2v. 1·81 (sd 0·22) m2, P = 0·01) and prevalence of hypertension (63 % v. 47 %, P = 0·10). Adjusting for age, sex, race and physical activity, it is found that vegetarians had greater echocardiographic mitral annular e' velocity (a measure of left ventricular (LV) relaxation) 7·44 v. 6·48 (non-vegetarian) cm/s (P = 0·011) and a yet greater contrast when vegans (7·66 cm/s, P = 0·011) were the group of interest. The ratio mid-to-late-diastolic mitral flow velocity (E/A) was also higher in vegans compared with non-vegetarians (1·02 and 0·84, respectively, P = 0·008). Mediation analyses suggested these associations may be partly related to higher blood pressures and BMI in the non-vegetarians. We conclude that vegetarians, especially vegans, appear to have better LV relaxation and fewer diastolic abnormalities than others. As dietary exposure is modifiable, one may speculate pending further investigation about the potential for reduction of stage B HF and later mortality.

Dairy foods, calcium intakes, and risk of incident prostate cancer in Adventist Health Study-2.

BACKGROUND: Prostate cancer is the most common noncutaneous cancer in American males. Causal links between dairy, or dietary calcium, and this cancer are considered suggestive but limited. OBJECTIVES: To evaluate these associations in a large North American cohort, including many with no (or very low) dairy intake and much calcium from nondairy sources. METHODS: A prospective cohort study of 28,737 Seventh-day Adventist men in the United States and Canada, of whom 6389 were of black ethnicity. Diet was measured by FFQ, and 275 male participants also provided repeated 24-h dietary recalls as a calibration substudy. Incident cancers were mainly found by matching with cancer registries. Analyses used multivariable proportional hazards regressions and regression calibration for some analyses. RESULTS: In total, 1254 (190 advanced) incident prostate cancer cases were found during an average 7.8 y of follow-up. Men at the 90th percentile of dairy intake (430 g/d) compared with the 10th percentile (20.2 g/d) had higher prostate cancer risk (HR: 1.27; 95% CI: 1.12, 1.43). Similar findings, comparing the same g/d intakes, were demonstrated for advanced prostate cancers (HR: 1.38; 95% CI: 1.02, 1.88), for nonadvanced cases (HR: 1.27; 95% CI: 1.11, 1.45), in black participants (HR: 1.24; 95% CI: 0.98, 1.58), and when excluding vegan participants (HR: 1.22; 95% CI: 1.03, 1.43). Calibrated dairy (g/d) regressions (all participants and all prostate cancers), adjusting for dietary measurement error, found a HR of 1.75 (95% CI: 1.32, 2.32). Comparing 90th percentile intake to zero intakes (uncalibrated), the HR was 1.62 (95% CI: 1.26, 2.05). There was no evidence of an effect of higher (905 mg/d) compared with lower (349 mg/d) intakes of nondairy calcium (HR: 1.16; 95% CI: 0.94, 1.44). CONCLUSIONS: Men with higher intake of dairy foods, but not nondairy calcium, had a higher risk of prostate cancer compared with men having lower intakes. Associations were nonlinear, suggesting greatest increases in risk at relatively low doses.

Vegetarian dietary patterns and the risk of colorectal cancers.

IMPORTANCE: Colorectal cancers are a leading cause of cancer mortality, and their primary prevention by diet is highly desirable. The relationship of vegetarian dietary patterns to colorectal cancer risk is not well established. OBJECTIVE: To evaluate the association between vegetarian dietary patterns and incident colorectal cancers. DESIGN, SETTING, AND PARTICIPANTS: The Adventist Health Study 2 (AHS-2) is a large, prospective, North American cohort trial including 96,354 Seventh-Day Adventist men and women recruited between January 1, 2002, and December 31, 2007. Follow-up varied by state and was indicated by the cancer registry linkage dates. Of these participants, an analytic sample of 77,659 remained after exclusions. Analysis was conducted using Cox proportional hazards regression, controlling for important demographic and lifestyle confounders. The analysis was conducted between June 1, 2014, and October 20, 2014. EXPOSURES: Diet was assessed at baseline by a validated quantitative food frequency questionnaire and categorized into 4 vegetarian dietary patterns (vegan, lacto-ovo vegetarian, pescovegetarian, and semivegetarian) and a nonvegetarian dietary pattern. MAIN OUTCOMES AND MEASURES: The relationship between dietary patterns and incident cancers of the colon and rectum; colorectal cancer cases were identified primarily by state cancer registry linkages. RESULTS: During a mean follow-up of 7.3 years, 380 cases of colon cancer and 110 cases of rectal cancer were documented. The adjusted hazard ratios (HRs) in all vegetarians combined vs nonvegetarians were 0.78 (95% CI, 0.64-0.95) for all colorectal cancers, 0.81 (95% CI, 0.65-1.00) for colon cancer, and 0.71 (95% CI, 0.47-1.06) for rectal cancer. The adjusted HR for colorectal cancer in vegans was 0.84 (95% CI, 0.59-1.19); in lacto-ovo vegetarians, 0.82 (95% CI, 0.65-1.02); in pescovegetarians, 0.57 (95% CI, 0.40-0.82); and in semivegetarians, 0.92 (95% CI, 0.62-1.37) compared with nonvegetarians. Effect estimates were similar for men and women and for black and nonblack individuals. CONCLUSIONS AND RELEVANCE: Vegetarian diets are associated with an overall lower incidence of colorectal cancers. Pescovegetarians in particular have a much lower risk compared with nonvegetarians. If such associations are causal, they may be important for primary prevention of colorectal cancers.