Cross-sectional and longitudinal comparisons of metabolic profiles between vegetarian and non-vegetarian subjects: a matched cohort study

Abstract

Several previous cross-sectional studies have shown that vegetarians have a better metabolic profile than non-vegetarians, suggesting that a vegetarian dietary pattern may help prevent chronic degenerative diseases. However, longitudinal studies on the impact of vegetarian diets on metabolic traits are scarce. We studied how several sub-types of vegetarian diets affect metabolic traits, including waist circumference, BMI, systolic blood pressure (SBP), diastolic blood pressure, fasting blood glucose, total cholesterol (TC), HDL, LDL, TAG and TC:HDL ratio, through both cross-sectional and longitudinal study designs. The study used the MJ Health Screening database, with data collected from 1994 to 2008 in Taiwan, which included 4415 lacto-ovo-vegetarians, 1855 lacto-vegetarians and 1913 vegans; each vegetarian was matched with five non-vegetarians based on age, sex and study site. In the longitudinal follow-up, each additional year of vegan diet lowered the risk of obesity by 7 % (95 % CI 0·88, 0·99), whereas each additional year of lacto-vegetarian diet lowered the risk of elevated SBP by 8 % (95 % CI 0·85, 0·99) and elevated glucose by 7 % (95 % CI 0·87, 0·99), and each additional year of ovo-lacto-vegetarian diet increased abnormal HDL by 7 % (95 % CI 1·03, 1·12), compared with non-vegetarians. In the cross-sectional comparisons, all sub-types of vegetarians had lower likelihoods of abnormalities compared with non-vegetarians on all metabolic traits (P < 0·001 for all comparisons), except for HDL and TAG. The better metabolic profile in vegetarians is partially attributable to lower BMI. With proper management of TAG and HDL, along with caution about the intake of refined carbohydrates and fructose, a plant-based diet may benefit all aspects of the metabolic profile.

A comparative study of metabolic profile, anthropometric parameters among vegetarians and non-vegetarians- do vegetarian diet have a cardio protective role?

“…15 This escalation in the prevalence of CVD has been attributed to the paradigm shift in life style including the changes in dietary pattern (more consumption of refined carbohydrates and saturated fats) and physical inactivity in association with progressive economic growth and urbanization. 16 Overweight and obesity are well known risk factor for CVD. 15 In Indian Migration Study, a study of rural and urban adult population, mean aged 40+ years, across four regions and 18 states of India, it was found that vegetarians had lower levels of lipids and blood pressure supporting the hypothesis that a vegetarian diet has potential cardiovascular health benefits.…”

“…A meta-analysis of comparison of vegetarian diets and omnivorous diets on plasma level of HDL cholesterol provides evidence indicating that there was no significant difference in HDL levels between vegetarians and non-vegetarians. 16 Also, meta-analysis study by Chiu et al showed that lack of meat in vegetarian diet does not play a major protective role against CVD. Also, egg, milk and other dairy products being a staple part of vegetarian diet contains cholesterol in excess (for example in egg yolk) whereas non-vegetarians mainly consume lean meat instead of fat meat that does not increase plasma cholesterol levels.…”

“…Also, egg, milk and other dairy products being a staple part of vegetarian diet contains cholesterol in excess (for example in egg yolk) whereas non-vegetarians mainly consume lean meat instead of fat meat that does not increase plasma cholesterol levels. 16 This may be a probable explanation for lower HDL-C among individuals who consume vegetarian diet.…”

“…18,19 It is also postulated that plasma variations in HDL-C concentration are determined by rate of production and the rate of catabolism of HDL particles. 16 Conventionally, this anthropometric and metabolic profile among vegetarians may be attributed mainly to their diet that is lower in fat, saturated fat and protein and higher in complex carbohydrates and dietary fiber than the usual omnivorous diet and hence they exhibit lower risk factors for CVD and Type 2 diabetes compared to omnivores. However, other factors like presence of natural antioxidants that prevent oxidative modification of LDL may equally play a role in reduction of CVD.…”

Truths, Myths and Needs of Special Diets: Attention-Deficit/Hyperactivity Disorder, Autism, Non-Celiac Gluten Sensitivity, and Vegetarianism

“…NCGS is a syndrome characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food in subjects that are not affected by either celiac disease or wheat allergy [43,44] . Epidemiological studies in developed countries have reported a prevalence of 0.6-6% [39,45,46] .…”