Risk of Osteoporosis and Anemia in Plant-Based Diets: A Systematic Review of Nutritional Deficiencies and Clinical Implications

The global shift toward plant-based diets is accelerating, driven by growing awareness of health, environmental, and ethical concerns. While these diets are linked to reduced risks of chronic diseases, emerging evidence highlights potential nutritional deficiencies, particularly in calcium, iron, and vitamin B12, that may compromise bone and hematologic health. This systematic review investigates the relationship between strict plant-based dietary practices and the risks of anemia and osteoporosis. Following PRISMA guidelines, we conducted a comprehensive search across four databases PubMed, Scopus, Web of Science, and Google Scholar using relevant search terms including "plant-based diet", "vegan", "vegetarian", "anemia", "osteoporosis", "vitamin B12 deficiency", "iron deficiency", and "calcium deficiency". We retrieved 1290 records; after removing 210 duplicates and screening 1080 records, 208 full-text articles were assessed. Ultimately, 76 studies met the eligibility criteria and were included in the review. Our synthesis reveals consistent evidence linking poorly planned plant-based diets to increased risk of iron-deficiency anemia and reduced bone mineral density. These findings show the importance of nutritional education, regular monitoring, and appropriate supplementation to support individuals following vegan or vegetarian diets in achieving long-term health.