The association of diet and thrombotic risk factors in healthy male vegetarians and meat-eaters

Abstract

Objective: The aim of this study was to assess thrombosis tendency in subjects who were habitual meat-eaters compared with those who were habitual vegetarians. Design: Cross-sectional comparision of habitual meat-eaters and habitual vegetarians. Setting: Free living subjects. Subjects: One hundred and thirty-nine healthy male subjects (vegans n 18, ovolacto vegetarians n 43, moderate-meat-eaters n 60 and high-meat-eaters n 18) aged 20 ± 55 y who were recruited in Melbourne. Outcome measures: Dietary intake was assessed using a semi-quantitative Food Frequency Questionnaire. The parameters of thrombosis were measured by standard methods. Results: Saturated fat and cholesterol intakes were signi®cantly higher and polyunsaturated fat (PUFA) was signi®cantly lower in the meat-eaters compared with vegetarians. In the meat-eaters, the platelet phospholipids AA levels were signi®cantly higher than in the vegetarians, but there was no increase in ex vivo platelet aggregation and plasma 11-dehydro thromboxane B 2 levels. Vegetarians, especially the vegans, had a signi®cantly increased mean collagen and ADP stimulated ex vivo whole blood platelet aggregation compared with meat-eaters. The vegan group had a signi®cantly higher mean platelet volume than the other three dietary groups. However, meat-eaters had a signi®cantly higher cluster of cardiovascular risk factors compared with vegetarians, including increased body mass index, waist to hip ratio, plasma total cholesterol (TC), triacylglycerol and LDL-C levels, ratio of TCaHDL-C and LDL-CaHDL-C and plasma factor VII activity. Conclusions: Consumption of meat is not associated with an increased platelet aggregation compared with vegetarian subjects.

Effects of Vegetarian Diets on Blood Lipids: A Systematic Review and Meta‐Analysis of Randomized Controlled Trials

“…Although a large number of cross‐sectional studies14, 15 have shown that concentrations of TC, LDL‐C, and TG were much lower in vegetarians than in omnivores, a few studies32, 33 have found no such relationships with HDL‐C and TG concentrations. A meta‐analysis of 12 observational studies with a total of 4177 participants revealed no evidence showing that HDL‐C concentrations differed in vegetarians and omnivores 34.…”

Influence of habitual diet on antioxidant status: a study in a population of vegetarians and omnivores

“…In total, 31 vegetarians and 58 omnivores, who satisfied inclusion/exclusion criteria and were willing to volunteer participated in the study. Vegetarians were defined as those who did not consume meat, chicken, fish or other flesh foods, any more than six times per year (Li et al, 1999). Among the vegetarian group, there were six vegans who also refrained from eating eggs and dairy products.…”

Effects of docosahexaenoic acid supplementation on blood lipids, estrogen metabolism, and in vivo oxidative stress in postmenopausal vegetarian women

“…Long-chain n-3 fatty acids have been found to have beneficial effects on the regulation of plasma lipid levels and cardiovascular function (Mori and Beilin, 2001). Higher levels of platelet aggregation were found in vegetarians when compared to their omnivorous counterparts (Li et al, 1999), and long-chain n-3 fatty acid supplementation has been shown to reduce platelet aggregation (Mezzano et al, 2000). DHA supplementation also induced a moderate reduction in the total or LDL-cholesterol:HDL-cholesterol ratio and a slight reduction in triglyceride concentration in vegetarians (Conquer and Holub, 1996).…”