Vegan Diet, Subnormal Vitamin B-12 Status and Cardiovascular Health

Abstract

Vegetarian diets have been associated with atherosclerosis protection, with healthier atherosclerosis risk profiles, as well as lower prevalence of, and mortality from, ischemic heart disease and stroke. However, there are few data concerning the possible cardiovascular effects of a vegan diet (with no meat, dairy or egg products). Vitamin B-12 deficiency is highly prevalent in vegetarians; this can be partially alleviated by taking dairy/egg products in lact-ovo-vegetarians. However, metabolic vitamin B-12 deficiency is highly prevalent in vegetarians in Australia, Germany, Italy and Austria, and in vegans (80%) in Hong Kong and India, where vegans rarely take vitamin B-12 fortified food or vitamin B-12 supplements. Similar deficiencies exist in northern Chinese rural communities consuming inadequate meat, egg or dairy products due to poverty or dietary habits. Vascular studies have demonstrated impaired arterial endothelial function and increased carotid intima-media thickness as atherosclerosis surrogates in such metabolic vitamin B-12 deficient populations, but not in lactovegetarians in China. Vitamin B-12 supplementation has a favourable impact on these vascular surrogates in Hong Kong vegans and in underprivileged communities in northern rural China. Regular monitoring of vitamin B-12 status is thus potentially beneficial for early detection and treatment of metabolic vitamin B-12 deficiency in vegans, and possibly for prevention of atherosclerosis-related diseases.

Opportunistic Screening of Vitamin B12 Deficiency in IT Professionals Presenting for Routine Health Check-up

“…As many studies [7,8] have already highlighted, the disorder is known to be significantly prevalent amongst vegetarian population. In our study, B12 deficiency prevalence was 47.5% (19/40) (p-value <0.05) amongst vegetarian subjects.…”

Beyond sports: Efficacy and safety of creatine supplementation in pathological or paraphysiological conditions of brain and muscle

“…46 Beside lack of intake with the diet, another possible reason for low creatine levels in subjects following a vegetarian or vegan diet is that creatine synthesis is impaired in subjects having vitamin B 12 deficiency, 47 a condition that is not infrequent among vegans and vegetarians. 48,49 Creatine administration has a greater ergogenic effect in vegetarian subjects than in nonvegetarian ones. 43,45 The administration of creatine at a dose of 0.3 g/kg/d (21 g in a man of 70 kg) for 5 days was able to normalize creatine muscle content, which was beforehand reduced by a lacto-ovo vegetarian diet.…”

Animal (De)liberation: Should the Consumption of Animal Products Be Banned?

“…Vegans must be careful, however, to avoid overconsumption of refined carbohydrates (as for example white-flour products, white rice, and sugar), as this reduces HDL, which removes excess LDL cholesterol from the bloodstream (O'Neill 2010, 202-203). As mentioned before, they must also be careful to maintain adequate levels of vitamins B12 and D, as well as a good balance of n-6 over n-3 fatty acids, as deficiencies in these domains have been associated with elevated risks of cardio-vascular disease (Li 2011;Woo et al 2014;Bouillon and Verlinden 2014).…”