Comparing Anemia Prevalence In Vegetarian And Omnivorous Diets A Systematic Review And Meta-Analysis
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Abstract
Background: In recent years, the prevalence of vegetarian and vegan diets has increased due to their associated health benefits. However, long-term avoidance of animal foods can lead to inadequate intake of essential nutrients like iron and vitamin B-12, critical for maintaining blood health. Iron deficiency is a widespread nutritional problem, especially in vegetarian diets, due to the reduced bioavailability of non-heme iron in plant foods. This study aimed to provide a detailed comparison of anemia frequency and other hematological parameters between vegetarian and omnivorous diets, thereby offering insights into the nutritional adequacy and health outcomes of these dietary habits.
Methods: The study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, utilizing a prospective cohort from the UK Biobank. Participants aged 40–69 years were investigated for anemia prevalence in vegetarian and omnivorous diets. Data collection included informed consent procedures, a touch-screen questionnaire addressing sociodemographic and lifestyle factors, and a computer-assisted personal interview. Blood samples were collected for complete blood cell counts and hematological assays. Statistical analysis involved linear regression models, adjusted for age, sex, menopausal status, and smoking status.
Results: The study found that vegetarians and other low or non-meat eaters had slightly lower age-adjusted hemoglobin concentrations and were more likely to be anemic compared to regular meat eaters. However, a well-balanced vegetarian diet did not significantly differ in iron-deficiency anemia incidence compared to omnivores. The study also noted differences in white blood cell parameters and platelet characteristics between diet groups, suggesting potential differences in immune function.
Conclusion: The research concluded that a well-planned vegetarian diet does not increase the risk of iron-deficiency anemia compared to omnivorous diets. The key is dietary quality and appropriate planning, ensuring sufficient iron intake to prevent deficiency and support overall health. The findings contribute to the discussion about the adequacy of vegetarian diets and their role in preventing chronic conditions.
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